Systems and Scale

Systems and Scale is the first of the six Carbon TIME units. If you are new to teaching Carbon TIME, read the Carbon TIME FAQ: Which Units Should I Teach? .

The goal of the Systems and Scale unit is to introduce students to organic matter and chemical energy (in the context of combustion) using the tools for reasoning and environmental literacy practices that students will engage with in other units. Students develop required capacity to distinguish organic matter from inorganic matter, and to understand how differences in the chemical make-up of materials influences how materials and energy are transformed and moved between systems.

The Systems and Scale Unit supports students in using core disciplinary ideas, science practices, and cross-cutting concepts to develop scientific explanations of how matter and energy are transformed during combustion of different organic materials.

Follow these steps to get ready to teach the Systems and Scale Unit

Lead Editor for 2019 Version

Kirsten D. Edwards, Department of Teacher Education, Michigan State University

Principal Authors

Hannah K. Miller, Education Department, Johnson State University

Jenny Dauer, School of Natural Resources, University of Nebraska-Lincoln

Christa Haverly, Department of Teacher Education, Michigan State University

Kirsten D. Edwards, Department of Teacher Edwards, Michigan State University

Christie Morrison Thomas, Department of Teacher Education, Michigan State University

Charles W. “Andy” Anderson, Department of Teacher Education, Michigan State University

Contributing Authors

Elizabeth Xeng de los Santos, Beth Covitt, Jennifer Doherty, Allison Freed, Wendy Johnson, Deborah Jordan, Craig Kohn, Lindsey Mohan, Joyce Parker, Elizabeth Tompkins, Nick Verbanic

Illustrations

Craig Douglas, Kendra Mojica

This research is supported in part by grants from the National Science Foundation: A Learning Progression-based System for Promoting Understanding of Carbon-transforming Processes (DRL 1020187) and Sustaining Responsive and Rigorous Teaching Based on Carbon TIME (NSF 1440988). Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation or the united States Department of Energy.

Contact the MSU Environmental Literacy Program for more information: EnvLit@msu.edu.

The Driving Question

The Systems and Scale Unit starts by asking students to express their ideas about the driving question about an anchoring phenomenon: What happens when ethanol burns? The unit helps students answer this question by using core disciplinary ideas, science practices, and cross-cutting concepts to develop scientific explanations of how matter and energy are transformed during combustion of different organic materials

Carbon is the Key!

In the unit, students learn to tell the story of how matter and energy are transformed as they move through systems where combustion of organic materials is occurring, including open flames and internal combustion engines. A particularly powerful strategy for explaining how flames transform matter and energy involves tracing carbon atoms. We have found that learning to use this strategy proficiently with flames—relatively simple systems—prepares students to study more complex living systems.

Students’ Roles and Science Practices

As students learn to answer the driving question by explaining how flames transform matter and energy, they play three different roles that encompass all of the Next Generation Science Standards science and engineering practices.

Questioners: Students explore the driving question, clarify, and generate more detailed questions.
Investigators: Students conduct two matter-tracing investigations of (a) soda water fizzing and (b) ethanol burning. They develop evidence-based arguments about key observations and patterns.
Explainers: Students construct model-based explanations of how matter and energy are transformed when organic materials burn.

The roles that students play are also embedded in the Carbon TIME Discourse Routine. The Discourse Routine guides how classroom discourse aimed first at divergent thinking and then at convergent thinking should be sequenced through the unit.

Good Explanations Answer the Three Questions

Students figure out how to answer the driving question by tracing the carbon-containing molecules in fuels through a series of movements and chemical changes inside flames. At each stage in these processes they answer Three Questions about what is happening: the Matter Movement Question, the Matter Change Question, and the Energy Change Question.

Note that, in Carbon TIME, crosscutting concepts serve as the “rules of grammar” for producing a scientific performance. With respect to organic materials burning, high quality explanations should attend to the following rules that are implied by crosscutting concepts. Explanations should attend to…

Scale by explaining events and phenomena at the appropriate scale (see more in the structure and function bullets below).
Systems and system models and energy and matter by following rules for tracing matter and energy through systems and system models. For example, neither energy nor matter should be created or destroyed as it moves into, through, or out of a system.
Structure and function by linking structures and functions in explanations at each scale.
- Macroscopic scale (tracing matter and energy through flames
- Atomic-molecular scale (tracing matter and energy through a chemical process—combustion—involving molecules with different structures and properties)

Below, we use the anchoring phenomenon of ethanol burning as an example of how students learn to answer the Three Questions for combustion of different organic materials.

The Matter Movement Question: Tracing Molecules Through Flames

Students learn to tell the following story of how carbon-containing molecules move through the flame in burning ethanol.

Ethanol (C₅H₂OH) evaporates and enters the flame, along with O₂ molecules from the air.
Carbon dioxide and water vapor leave the flame.

The Matter Change and Energy Change Questions: Explaining How Combustion Changes Organic Materials

Matter movement is an essential part of the story, but not the whole story. To answer the driving question, students learn to explain chemical changes that occur inside flames:

Matter Change: Students explain how the reactant molecules (ethanol and oxygen) break apart in the flame, and how their atoms then bond together to create new products (carbon dioxide molecules and water molecules).
Energy Change: Students explain how the chemical energy in the reactant molecules, indicated by high-energy C-C and C-H bonds, is released when the products form lower-energy C=O and H-O bonds, releasing energy in the form of heat, light, and movement of air.

Students practice their explanations using multiple representations: (a) hand-on molecular models, (b) PowerPoint animations, (c) a chemical equation (C₂H₅OH + 3O₂ -> 2CO₂ + 3H₂O), and (d) written paragraphs.

How Much Detail?

There are more complicated and more scientifically accurate ways of talking about chemical bonds and about changes in energy; we discuss some of those in detail in our educator resource: Carbon TIME Content Simplifications. But our learning progression research has shown that there is an important tradeoff here—many students get lost in the details and never learn a basic coherent story that answers the driving question. The Next Generation Science Standards take a clear position on this tradeoff; a coherent story based on principles such as matter and energy conservation is more important than the details. Consult the Unit Sequence tab to decide how much detail is appropriate for your students.

Before beginning the Systems and Scale Unit, you need to decide what to teach and importantly, what not to teach! Use this page to choose the unit sequence that’s most appropriate for your students.

Optional activities in the Systems and Scale Unit are designed to provide supportive learning opportunities for students who have not previously studied or who are still working to develop proficiency with regard to reasoning about scale and chemical change. Use your professional judgment to decide whether or not to teach each optional lesson or activity.

Unless otherwise noted in the table below, all activities in the unit should be taught.

Download Systems and Scale Unit Sequence Document

Here, we present two ways to think about how lessons are sequenced in the Systems and Scale Unit. The instructional model, immediately below, emphasizes how students take on roles of questioner, investigator, and explainer to learn and apply scientific models they can use to answer the driving question. Further below, the Unit Storyline Chart highlights the central question, activity, and answer that students engage with in each lesson of the Systems and Scale Unit.

Instructional Model

Like all Carbon TIME units, this unit follows an instructional model (IM) designed to support teaching that helps students achieve mastery at answering the driving question through use of disciplinary content, science practices, and crosscutting concepts. To learn more about this design, see the Carbon TIME instructional model.

The core of the Carbon TIME IM is the Observation, Patterns, Models (OPM) triangle, which summarizes key aspects to be attended to as the class engages in unit inquiry and explanation. The OPM triangle for the Systems and Scale Unit, shown below, articulates the key observations students make during the unit investigation, the key patterns they identify through analyzing their investigation data, and the central scientific model that can be used to answer the unit’s driving question. During the inquiry portions of the unit (Lessons 3 and 4), the class moves from making observations to identifying patterns, eventually using these patterns to make evidence-based arguments. During the explanation portion of the unit (Lessons 4 and 5), the class learns the atomic-molecular model, makes connections across scales, and uses atomic-molecular model to explain how animals grow, move, and function. Across the unit, classroom discourse is a necessary part of 3-dimensional Carbon TIME learning. The Carbon TIME Discourse Routine document provides guidance for scaffolding this discourse in lessons.

Unit Storyline Chart

Another way to familiarize yourself with the sequence of lessons in the Systems and Scale Unit is with the Unit Storyline Chart depicted below. The Unit Storyline Chart summarizes a unit phenomenon-based driving question associated with each lesson, what classes will do in each lesson to address the question, what conclusions they will come to, and how they will transition to a subsequent lesson.

Download Unit IM and Storyline Chart

The tables below show goals for this unit in two forms. A list of Next Generation Science Standards (NGSS) addressed by this unit is followed by a table showing specific target performances for each activity.

Next Generation Science Standards

The Next Generation Science Standards (NGSS) performance expectations that middle and high school students can achieve through completing the Animals Unit are listed below. To read a discussion of how the Carbon TIME project is designed to help students achieve the performances represented in the NGSS, please see Three-dimensional Learning in Carbon TIME.

High School

Matter and its Interactions. HS-PS1-4. Develop a model to illustrate that the release or absorption of energy from a chemical reaction system depends upon the changes in total bond energy.
Matter and its Interactions. HS-PS1-7. Use mathematical representations to support the claim that atoms, and therefore mass, are conserved during a chemical reaction.

Middle School

Matter and its Interactions. MS-PS1-1. Develop models to describe the atomic composition of simple molecules and extended structures.
Matter and its Interactions. MS-PS1-2. Analyze and interpret data on the properties of substances before and after the substances interact to determine if a chemical reaction has occurred.
Matter and its Interactions. MS-PS1-5. Develop and use a model to describe how the total number of atoms does not change in a chemical reaction and thus mass is conserved.

Target Performances for Each Activity

All Carbon TIME units are organized around a common purpose: assessing and scaffolding students’ three-dimensional engagement with phenomena. Every Carbon TIME activity has its specific expectation for students’ three-dimensional engagement with phenomena, what we call its target performance. Each activity also includes tools and strategies that teachers can use to asses and scaffold the target performance in rigorous and responsive ways.

The target performances for each activity in the Systems and Scale unit are listed in the table below.

Download Document

Materials List

Download All Materials

Download Materials to Purchase List

Resources You Provide

Activity 1.1: Systems and Scale Unit Pretest (20 min)

Pencils (1 per student)

Activity 1.2: Expressing Ideas about Ethanol Burning (40 min)

sticky notes (1 per student)
ethanol, 95% (10-15 ml)
water (10-15 ml)
lighter (1)
Petri dish, glass (1)
Petri dish, plastic (1)

Activity 2.1: Powers of Ten Video and Discussion (30 min)

(Optional) Activity 2.2: From Big to Small (30 min)

Activity 2.3: Zooming into Air (30 min)

piece of paper (1 per student)

Activity 2.4: Atoms and Molecules Quiz and Discussion (30 min)

pencils (1 per student)

Activity 2.5: Using a Digital Balance and BTB (30 min)

BTB, blue (1 cup per group of four students)
clear plastic cups (1 per group of four students)
digital balance (1 per group of four students)
paper clips (10 per group of four students)
safety glasses (1 per group of four students)
straws (1 per group of four students)

Activity 3.1: Predictions about Soda Water Fizzing (20 min)

Petri dish, plastic (1 per class)
Soda water (1 cup per class)

Activity 3.2: Observing Soda Water Fizzing (30 min)

BTB, blue (less than 1 cup per group of four students)
digital balance (1 per group of four students)
Petri dish, plastic (2 per group of four students)
sealable, 9.5-Cup container (1 per group of four students)
soda water (less than 1 cup per group of four students)
(Optional) Molecular modeling kits
(From previous activity) 3.1 Predictions and Planning Tool for Soda Water Fizzing

Activity 3.3: Evidence-Based Arguments for Soda Water Fizzing (45 min)

(From Previous Activity) 3.2 Observing Soda Water Fizzing Worksheet
(From Previous Activity) 3.2 Soda Water Fizzing Class Results 11 x 17 Poster (or spreadsheet)

Activity 3.4: Molecular Models for Soda Water Fizzing (45 min)

molecular model kit (1 per pair of students )

Activity 3.5: Explaining Soda Water Fizzing (40 min)

(from previous activity) 3.3 Evidence-Based Arguments Tool for Soda Water Fizzing

Activity 4.1: Predictions about Ethanol Burning (30 min)

(From previous activity) Students’ ideas and questions they shared in Activity 1.2 Expressing Ideas Tool for Ethanol Burning
(From previous activity) 1.2 Expressing Ideas and Questions Tool for Ethanol Burning
Video of demonstration of ethanol burning

Activity 4.2: Observing Ethanol Burning (30 min)

BTB, blue (less than 1 cup per group)
(optional) BTB, yellow (less than 1 cup per group)
Digital balance (1 per group of four students)
Ethanol, 95% (10-15 ml per group)
Large plastic container with aluminum foil taped inside to protect the bottom from the ethanol flame (1 per group of four students)
Lighter (1 per group of four students)
Petri dish, glass (1 per group of four students)
Petri dish, plastic (1 per group of four students)
Safety glasses (1 per student)
(Optional) Molecular modeling kits
(From previous activity) 4.1 Predictions and Planning Tool for Ethanol Burning with student answers

Activity 4.3: Evidence-Based Arguments for Ethanol Burning (50 min)

(From Previous Activity) 4.2 Ethanol Burning Class Results 11 x 17 Poster (or spreadsheet)
(From Previous Activity) 4.2 Observing Ethanol Burning Worksheet

Activity 4.4: Molecular Models for Ethanol Burning (50 min)

molecular model kit (1 per pair of students)
scissors (1 per pair of students)
twist ties (at least 12 per pair of students)

Activity 4.5: Explaining Ethanol Burning (40 min)

(from previous activity) 4.3 Evidence-Based Arguments Tool for Ethanol Burning

Activity 5.1: Molecular Modeling for Methane Burning (40 min)

molecular modeling kit (1 per pair of students)
twist ties (12 per pair of students)

(Optional) Activity 5.2: Explaining Methane Burning (40 min)

Activity 5.3: Preparing for Future Units – Organic vs. Inorganic (40 min)

(From Previous Activity) 1.2 Expressing Ideas and Questions Tool for Ethanol Burning with student ideas

Activity 5.4: Explaining Other Examples of Combustion (50 min)

Activity 5.5: Systems and Scale Unit Posttest (20 min)

Pencils (1 per student)

Resources Provided

Activity 1.1: Systems and Scale Unit Pretest (20 min)

1.1 Systems and Scale Unit Pretest (1 per student)
1.1 Assessing Systems and Scale Unit Pretest

Activity 1.2: Expressing Ideas about Ethanol Burning (40 min)

Activity 2.1: Powers of Ten Video and Discussion (30 min)

(Optional) Activity 2.2: From Big to Small (30 min)

2.2 Powers of Ten Cards (1 per group)

Activity 2.3: Zooming into Air (30 min)

2.3 Zooming Into Air PPT

Activity 2.4: Atoms and Molecules Quiz and Discussion (30 min)

2.4 Atoms and Molecules Quiz (1 per student)
2.4 Grading the Atoms and Molecules Quiz (1 per teacher)

Activity 2.5: Using a Digital Balance and BTB (30 min)

Activity 3.1: Predictions about Soda Water Fizzing (20 min)

Activity 3.2: Observing Soda Water Fizzing (30 min)

3.2 Soda Water Fizzing Class Results 11 x 17 Poster (or spreadsheet)(1 per class)
3.2 Observing Soda Water Fizzing Worksheet (1 per student)
3.2 Assessing the Observing Soda Water Fizzing Worksheet (1 per group)
3.2 Observing Soda Water PPT (1 per class)

Activity 3.3: Evidence-Based Arguments for Soda Water Fizzing (45 min)

Activity 3.4: Molecular Models for Soda Water Fizzing (45 min)

Activity 3.5: Explaining Soda Water Fizzing (40 min)

Activity 4.1: Predictions about Ethanol Burning (30 min)

4.1 Predictions about Ethanol Burning PPT
4.1 Predictions and Planning Tool for Ethanol Burning (1 per student)
4.1 Assessing the Predictions and Planning Tool for Ethanol Burning
4.1 Good Explanations of Chemical Change Reading (1 per student)

Activity 4.2: Observing Ethanol Burning (30 min)

4.2 Ethanol Burning Class Results 11 x 17 Poster (or spreadsheet) (1 per class)
4.2 Observing Ethanol Burning Worksheet (1 per student)
4.2 Grading the Observing Ethanol Burning Worksheet (1 per group)
4.2 Observing Ethanol Burning PPT (1 per class)

Activity 4.3: Evidence-Based Arguments for Ethanol Burning (50 min)

Activity 4.4: Molecular Models for Ethanol Burning (50 min)

4.4 Molecular Models for Ethanol Burning Worksheet (1 per student)
4.4 Grading the Molecular Models for Ethanol Burning Worksheet
4.4 Molecular Models for Ethanol Burning PPT
4.4 Molecular Models for Ethanol Burning Reading (1 per student)
(Optional) 4.4 Alternative Flame Molecular Model Placemat (1 per pair of students)
Carbon TIME Molecular Modeling Ethanol Video

Activity 4.5: Explaining Ethanol Burning (40 min)

4.5 Explanations Tool for Ethanol Burning
4.5 Explaining Ethanol Burning PPT
4.5 Grading the Explanations Tool for Ethanol Burning
(Optional) 4.5 What Happens When Ethanol Burns? Reading (1 per student)
(Optional) 4.5 Matter Tracing Tool
(Optional) Grading the 4.5 Matter Tracing Tool

Activity 5.1: Molecular Modeling for Methane Burning (40 min)

5.1 Molecular Models for Methane Burning PPT
(Optional) 5.1 Molecular Models for Methane Burning Worksheet (1 per student)
(Optional) 5.1 Grading Molecular Models for Methane Burning Worksheet

(Optional) Activity 5.2: Explaining Methane Burning (40 min)

Activity 5.3: Preparing for Future Units – Organic vs. Inorganic (40 min)

5.3 Organic vs. Inorganic PPT
5.3 Materials Cards (1 set per pair of students)
5.3 Organic vs. Inorganic Worksheet (1 per student)
5.3 Grading the Organic vs. Inorganic Worksheet
(Optional) 5.3 More About Chemical Energy Reading (1 per student)

Activity 5.4: Explaining Other Examples of Combustion (50 min)

Activity 5.5: Systems and Scale Unit Posttest (20 min)

Recurring Resources

Activity 1.1: Systems and Scale Unit Pretest (20 min)

Activity 1.2: Expressing Ideas about Ethanol Burning (40 min)

Questions, Connections, Questions Student Reading Strategy
Learning Tracking Tool for Systems and Scale (1 per student)
Assessing the Learning Tracking Tool for Systems and Scale
(Optional) Big Idea Probe: Fill 'Er Up (1 per student)
(Optional) Assessing the Big Idea Probe: Fill 'Er Up
Using Big Idea Probes

Activity 2.1: Powers of Ten Video and Discussion (30 min)

Learning Tracking Tool for Systems and Scale (1 per student)
Assessing the Learning Tracking Tool for Systems and Scale

(Optional) Activity 2.2: From Big to Small (30 min)

Powers of Ten 11 x 17 Poster (1 per class)
Powers of Ten with Pictures 11 x 17 Poster (1 per class)

Activity 2.3: Zooming into Air (30 min)

Learning Tracking Tool for Systems and Scale (1 per student)
Assessing the Learning Tracking Tool for Systems and Scale

Activity 2.4: Atoms and Molecules Quiz and Discussion (30 min)

Molecule 11 x 17 Poster (1 per class)

Activity 2.5: Using a Digital Balance and BTB (30 min)

Learning Tracking Tool for Systems and Scale (1 per student)
Assessing the Learning Tracking Tool for Systems and Scale
(Optional) BTB Color Handout
BTB Information and Instructions Handout

Activity 3.1: Predictions about Soda Water Fizzing (20 min)

Activity 3.2: Observing Soda Water Fizzing (30 min)

BTB Information and Instructions Handout
(Optional) BTB Color Handout (1 per group)

Activity 3.3: Evidence-Based Arguments for Soda Water Fizzing (45 min)

Learning Tracking Tool for Systems and Scale (1 per student)
Assessing the Learning Tracking Tool for Systems and Scale

Activity 3.4: Molecular Models for Soda Water Fizzing (45 min)

Activity 3.5: Explaining Soda Water Fizzing (40 min)

Activity 4.1: Predictions about Ethanol Burning (30 min)

Three Questions 11x17 Poster (1 per class)
Three Questions Handout (Color Version)
Three Questions Handout (BW Version)
Questions, Connections, Questions Student Reading Strategy
(Optional) Investigation Planning Tool
Burning Ethanol Video

Activity 4.2: Observing Ethanol Burning (30 min)

(Optional) BTB Color Handout
(Optional) BTB Information and Instructions Handout
Three Questions Handout (Color Version)
Three Questions Handout (BW Version)
Burning Ethanol Video

Activity 4.3: Evidence-Based Arguments for Ethanol Burning (50 min)

Three Questions Handout (Color Version) (1 per student)
Three Questions Handout (BW Version) (1 per student)
Learning Tracking Tool for Systems and Scale (1 per student)
Assessing the Learning Tracking Tool for Systems and Scale

Activity 4.4: Molecular Models for Ethanol Burning (50 min)

Learning Tracking Tool for Systems and Scale (1 per student)
Assessing the Learning Tracking Tool for Systems and Scale
Questions, Connections, Questions Student Reading Strategy
Using Big Idea Probes
Forms of Energy Cards (1 set pair of students)
Molecular Models 11 x 17 Placemat (1 per pair of students)

Activity 4.5: Explaining Ethanol Burning (40 min)

Three Questions Handout (Color Version)
Three Questions Handout (BW Version)
Questions, Connections, Questions Student Reading Strategy
(Optional) Big Idea Probe: Fill 'Er Up (1 per student)
(Optional) Assessing the Big Idea Probe: Fill 'Er Up
(Optional) Example Systems and Scale Explanations Handout (1 per student or per group)

Activity 5.1: Molecular Modeling for Methane Burning (40 min)

(Optional) Forms of Energy Cards (1 per pair of students)
(Optional) Molecular Models 11 x 17 Placemat (1 per pair of students)

(Optional) Activity 5.2: Explaining Methane Burning (40 min)

Three Questions Handout (Color Version) (1 per student)
Three Questions Handout (BW Version) (1 per student)
(Optional) Example Systems and Scale Explanations Handout (1 per student or per group)

Activity 5.3: Preparing for Future Units – Organic vs. Inorganic (40 min)

Learning Tracking Tool for Systems and Scale (1 per student)
Assessing the Learning Tracking Tool for Systems and Scale

Activity 5.4: Explaining Other Examples of Combustion (50 min)

Three Questions Handout (Color Version) (1 per student)
Three Questions Handout (BW Version) (1 per student)
Learning Tracking Tool for Systems and Scale (1 per student)
Assessing the Learning Tracking Tool for Systems and Scale
(Optional) Big Idea Probe: Fill 'Er Up
(Optional) Assessing the Big Idea Probe: Fill 'Er Up

Activity 5.5: Systems and Scale Unit Posttest (20 min)

Download PDF Unit Front Matter

Systems and Scale is the first of the six Carbon TIME units. If you are new to teaching Carbon TIME, read the Carbon TIME FAQ: Which Units Should I Teach? .

Follow these steps to get ready to teach the Systems and Scale Unit

Lead Editor for 2019 Version

Kirsten D. Edwards, Department of Teacher Education, Michigan State University

Principal Authors

Hannah K. Miller, Education Department, Johnson State University

Jenny Dauer, School of Natural Resources, University of Nebraska-Lincoln

Christa Haverly, Department of Teacher Education, Michigan State University

Kirsten D. Edwards, Department of Teacher Edwards, Michigan State University

Christie Morrison Thomas, Department of Teacher Education, Michigan State University

Charles W. “Andy” Anderson, Department of Teacher Education, Michigan State University

Contributing Authors

Elizabeth Xeng de los Santos, Beth Covitt, Jennifer Doherty, Allison Freed, Wendy Johnson, Deborah Jordan, Craig Kohn, Lindsey Mohan, Joyce Parker, Elizabeth Tompkins, Nick Verbanic

Illustrations

Craig Douglas, Kendra Mojica

Contact the MSU Environmental Literacy Program for more information: EnvLit@msu.edu.

The Driving Question

Carbon is the Key!

Students’ Roles and Science Practices

Questioners: Students explore the driving question, clarify, and generate more detailed questions.
Investigators: Students conduct two matter-tracing investigations of (a) soda water fizzing and (b) ethanol burning. They develop evidence-based arguments about key observations and patterns.
Explainers: Students construct model-based explanations of how matter and energy are transformed when organic materials burn.

Good Explanations Answer the Three Questions

Scale by explaining events and phenomena at the appropriate scale (see more in the structure and function bullets below).
Systems and system models and energy and matter by following rules for tracing matter and energy through systems and system models. For example, neither energy nor matter should be created or destroyed as it moves into, through, or out of a system.
Structure and function by linking structures and functions in explanations at each scale.
- Macroscopic scale (tracing matter and energy through flames
- Atomic-molecular scale (tracing matter and energy through a chemical process—combustion—involving molecules with different structures and properties)

Below, we use the anchoring phenomenon of ethanol burning as an example of how students learn to answer the Three Questions for combustion of different organic materials.

The Matter Movement Question: Tracing Molecules Through Flames

Students learn to tell the following story of how carbon-containing molecules move through the flame in burning ethanol.

Ethanol (C₅H₂OH) evaporates and enters the flame, along with O₂ molecules from the air.
Carbon dioxide and water vapor leave the flame.

The Matter Change and Energy Change Questions: Explaining How Combustion Changes Organic Materials

Matter movement is an essential part of the story, but not the whole story. To answer the driving question, students learn to explain chemical changes that occur inside flames:

Matter Change: Students explain how the reactant molecules (ethanol and oxygen) break apart in the flame, and how their atoms then bond together to create new products (carbon dioxide molecules and water molecules).
Energy Change: Students explain how the chemical energy in the reactant molecules, indicated by high-energy C-C and C-H bonds, is released when the products form lower-energy C=O and H-O bonds, releasing energy in the form of heat, light, and movement of air.

How Much Detail?

Optional activities in the Systems and Scale Unit are designed to provide supportive learning opportunities for students who have not previously studied or who are still working to develop proficiency with regard to reasoning about scale and chemical change. Use your professional judgment to decide whether or not to teach each optional lesson or activity.

Unless otherwise noted in the table below, all activities in the unit should be taught.

Download Systems and Scale Unit Sequence Document

Instructional Model

Unit Storyline Chart

Download Unit IM and Storyline Chart

Next Generation Science Standards

High School

Matter and its Interactions. HS-PS1-4. Develop a model to illustrate that the release or absorption of energy from a chemical reaction system depends upon the changes in total bond energy.
Matter and its Interactions. HS-PS1-7. Use mathematical representations to support the claim that atoms, and therefore mass, are conserved during a chemical reaction.

Middle School

Matter and its Interactions. MS-PS1-1. Develop models to describe the atomic composition of simple molecules and extended structures.
Matter and its Interactions. MS-PS1-2. Analyze and interpret data on the properties of substances before and after the substances interact to determine if a chemical reaction has occurred.
Matter and its Interactions. MS-PS1-5. Develop and use a model to describe how the total number of atoms does not change in a chemical reaction and thus mass is conserved.

Target Performances for Each Activity

The target performances for each activity in the Systems and Scale unit are listed in the table below.

Download Document

Materials List

Download All Materials

Download Materials to Purchase List

Resources You Provide

Activity 1.1: Systems and Scale Unit Pretest (20 min)

Pencils (1 per student)

Activity 1.2: Expressing Ideas about Ethanol Burning (40 min)

sticky notes (1 per student)
ethanol, 95% (10-15 ml)
water (10-15 ml)
lighter (1)
Petri dish, glass (1)
Petri dish, plastic (1)

Activity 2.1: Powers of Ten Video and Discussion (30 min)

(Optional) Activity 2.2: From Big to Small (30 min)

Activity 2.3: Zooming into Air (30 min)

piece of paper (1 per student)

Activity 2.4: Atoms and Molecules Quiz and Discussion (30 min)

pencils (1 per student)

Activity 2.5: Using a Digital Balance and BTB (30 min)

BTB, blue (1 cup per group of four students)
clear plastic cups (1 per group of four students)
digital balance (1 per group of four students)
paper clips (10 per group of four students)
safety glasses (1 per group of four students)
straws (1 per group of four students)

Activity 3.1: Predictions about Soda Water Fizzing (20 min)

Petri dish, plastic (1 per class)
Soda water (1 cup per class)

Activity 3.2: Observing Soda Water Fizzing (30 min)

BTB, blue (less than 1 cup per group of four students)
digital balance (1 per group of four students)
Petri dish, plastic (2 per group of four students)
sealable, 9.5-Cup container (1 per group of four students)
soda water (less than 1 cup per group of four students)
(Optional) Molecular modeling kits
(From previous activity) 3.1 Predictions and Planning Tool for Soda Water Fizzing

Activity 3.3: Evidence-Based Arguments for Soda Water Fizzing (45 min)

(From Previous Activity) 3.2 Observing Soda Water Fizzing Worksheet
(From Previous Activity) 3.2 Soda Water Fizzing Class Results 11 x 17 Poster (or spreadsheet)

Activity 3.4: Molecular Models for Soda Water Fizzing (45 min)

molecular model kit (1 per pair of students )

Activity 3.5: Explaining Soda Water Fizzing (40 min)

(from previous activity) 3.3 Evidence-Based Arguments Tool for Soda Water Fizzing

Activity 4.1: Predictions about Ethanol Burning (30 min)

(From previous activity) Students’ ideas and questions they shared in Activity 1.2 Expressing Ideas Tool for Ethanol Burning
(From previous activity) 1.2 Expressing Ideas and Questions Tool for Ethanol Burning
Video of demonstration of ethanol burning

Activity 4.2: Observing Ethanol Burning (30 min)

BTB, blue (less than 1 cup per group)
(optional) BTB, yellow (less than 1 cup per group)
Digital balance (1 per group of four students)
Ethanol, 95% (10-15 ml per group)
Large plastic container with aluminum foil taped inside to protect the bottom from the ethanol flame (1 per group of four students)
Lighter (1 per group of four students)
Petri dish, glass (1 per group of four students)
Petri dish, plastic (1 per group of four students)
Safety glasses (1 per student)
(Optional) Molecular modeling kits
(From previous activity) 4.1 Predictions and Planning Tool for Ethanol Burning with student answers

Activity 4.3: Evidence-Based Arguments for Ethanol Burning (50 min)

(From Previous Activity) 4.2 Ethanol Burning Class Results 11 x 17 Poster (or spreadsheet)
(From Previous Activity) 4.2 Observing Ethanol Burning Worksheet

Activity 4.4: Molecular Models for Ethanol Burning (50 min)

molecular model kit (1 per pair of students)
scissors (1 per pair of students)
twist ties (at least 12 per pair of students)

Activity 4.5: Explaining Ethanol Burning (40 min)

(from previous activity) 4.3 Evidence-Based Arguments Tool for Ethanol Burning

Activity 5.1: Molecular Modeling for Methane Burning (40 min)

molecular modeling kit (1 per pair of students)
twist ties (12 per pair of students)

(Optional) Activity 5.2: Explaining Methane Burning (40 min)

Activity 5.3: Preparing for Future Units – Organic vs. Inorganic (40 min)

(From Previous Activity) 1.2 Expressing Ideas and Questions Tool for Ethanol Burning with student ideas

Activity 5.4: Explaining Other Examples of Combustion (50 min)

Activity 5.5: Systems and Scale Unit Posttest (20 min)

Pencils (1 per student)

Resources Provided

Activity 1.1: Systems and Scale Unit Pretest (20 min)

1.1 Systems and Scale Unit Pretest (1 per student)
1.1 Assessing Systems and Scale Unit Pretest

Activity 1.2: Expressing Ideas about Ethanol Burning (40 min)

Activity 2.1: Powers of Ten Video and Discussion (30 min)

(Optional) Activity 2.2: From Big to Small (30 min)

2.2 Powers of Ten Cards (1 per group)

Activity 2.3: Zooming into Air (30 min)

2.3 Zooming Into Air PPT

Activity 2.4: Atoms and Molecules Quiz and Discussion (30 min)

2.4 Atoms and Molecules Quiz (1 per student)
2.4 Grading the Atoms and Molecules Quiz (1 per teacher)

Activity 2.5: Using a Digital Balance and BTB (30 min)

Activity 3.1: Predictions about Soda Water Fizzing (20 min)

Activity 3.2: Observing Soda Water Fizzing (30 min)

3.2 Soda Water Fizzing Class Results 11 x 17 Poster (or spreadsheet)(1 per class)
3.2 Observing Soda Water Fizzing Worksheet (1 per student)
3.2 Assessing the Observing Soda Water Fizzing Worksheet (1 per group)
3.2 Observing Soda Water PPT (1 per class)

Activity 3.3: Evidence-Based Arguments for Soda Water Fizzing (45 min)

Activity 3.4: Molecular Models for Soda Water Fizzing (45 min)

Activity 3.5: Explaining Soda Water Fizzing (40 min)

Activity 4.1: Predictions about Ethanol Burning (30 min)

4.1 Predictions about Ethanol Burning PPT
4.1 Predictions and Planning Tool for Ethanol Burning (1 per student)
4.1 Assessing the Predictions and Planning Tool for Ethanol Burning
4.1 Good Explanations of Chemical Change Reading (1 per student)

Activity 4.2: Observing Ethanol Burning (30 min)

4.2 Ethanol Burning Class Results 11 x 17 Poster (or spreadsheet) (1 per class)
4.2 Observing Ethanol Burning Worksheet (1 per student)
4.2 Grading the Observing Ethanol Burning Worksheet (1 per group)
4.2 Observing Ethanol Burning PPT (1 per class)

Activity 4.3: Evidence-Based Arguments for Ethanol Burning (50 min)

Activity 4.4: Molecular Models for Ethanol Burning (50 min)

4.4 Molecular Models for Ethanol Burning Worksheet (1 per student)
4.4 Grading the Molecular Models for Ethanol Burning Worksheet
4.4 Molecular Models for Ethanol Burning PPT
4.4 Molecular Models for Ethanol Burning Reading (1 per student)
(Optional) 4.4 Alternative Flame Molecular Model Placemat (1 per pair of students)
Carbon TIME Molecular Modeling Ethanol Video

Activity 4.5: Explaining Ethanol Burning (40 min)

4.5 Explanations Tool for Ethanol Burning
4.5 Explaining Ethanol Burning PPT
4.5 Grading the Explanations Tool for Ethanol Burning
(Optional) 4.5 What Happens When Ethanol Burns? Reading (1 per student)
(Optional) 4.5 Matter Tracing Tool
(Optional) Grading the 4.5 Matter Tracing Tool

Activity 5.1: Molecular Modeling for Methane Burning (40 min)

5.1 Molecular Models for Methane Burning PPT
(Optional) 5.1 Molecular Models for Methane Burning Worksheet (1 per student)
(Optional) 5.1 Grading Molecular Models for Methane Burning Worksheet

(Optional) Activity 5.2: Explaining Methane Burning (40 min)

Activity 5.3: Preparing for Future Units – Organic vs. Inorganic (40 min)

5.3 Organic vs. Inorganic PPT
5.3 Materials Cards (1 set per pair of students)
5.3 Organic vs. Inorganic Worksheet (1 per student)
5.3 Grading the Organic vs. Inorganic Worksheet
(Optional) 5.3 More About Chemical Energy Reading (1 per student)

Activity 5.4: Explaining Other Examples of Combustion (50 min)

Activity 5.5: Systems and Scale Unit Posttest (20 min)

Recurring Resources

Activity 1.1: Systems and Scale Unit Pretest (20 min)

Activity 1.2: Expressing Ideas about Ethanol Burning (40 min)

Questions, Connections, Questions Student Reading Strategy
Learning Tracking Tool for Systems and Scale (1 per student)
Assessing the Learning Tracking Tool for Systems and Scale
(Optional) Big Idea Probe: Fill 'Er Up (1 per student)
(Optional) Assessing the Big Idea Probe: Fill 'Er Up
Using Big Idea Probes

Activity 2.1: Powers of Ten Video and Discussion (30 min)

Learning Tracking Tool for Systems and Scale (1 per student)
Assessing the Learning Tracking Tool for Systems and Scale

(Optional) Activity 2.2: From Big to Small (30 min)

Powers of Ten 11 x 17 Poster (1 per class)
Powers of Ten with Pictures 11 x 17 Poster (1 per class)

Activity 2.3: Zooming into Air (30 min)

Learning Tracking Tool for Systems and Scale (1 per student)
Assessing the Learning Tracking Tool for Systems and Scale

Activity 2.4: Atoms and Molecules Quiz and Discussion (30 min)

Molecule 11 x 17 Poster (1 per class)

Activity 2.5: Using a Digital Balance and BTB (30 min)

Learning Tracking Tool for Systems and Scale (1 per student)
Assessing the Learning Tracking Tool for Systems and Scale
(Optional) BTB Color Handout
BTB Information and Instructions Handout

Activity 3.1: Predictions about Soda Water Fizzing (20 min)

Activity 3.2: Observing Soda Water Fizzing (30 min)

BTB Information and Instructions Handout
(Optional) BTB Color Handout (1 per group)

Activity 3.3: Evidence-Based Arguments for Soda Water Fizzing (45 min)

Learning Tracking Tool for Systems and Scale (1 per student)
Assessing the Learning Tracking Tool for Systems and Scale

Activity 3.4: Molecular Models for Soda Water Fizzing (45 min)

Activity 3.5: Explaining Soda Water Fizzing (40 min)

Activity 4.1: Predictions about Ethanol Burning (30 min)

Three Questions 11x17 Poster (1 per class)
Three Questions Handout (Color Version)
Three Questions Handout (BW Version)
Questions, Connections, Questions Student Reading Strategy
(Optional) Investigation Planning Tool
Burning Ethanol Video

Activity 4.2: Observing Ethanol Burning (30 min)

(Optional) BTB Color Handout
(Optional) BTB Information and Instructions Handout
Three Questions Handout (Color Version)
Three Questions Handout (BW Version)
Burning Ethanol Video

Activity 4.3: Evidence-Based Arguments for Ethanol Burning (50 min)

Three Questions Handout (Color Version) (1 per student)
Three Questions Handout (BW Version) (1 per student)
Learning Tracking Tool for Systems and Scale (1 per student)
Assessing the Learning Tracking Tool for Systems and Scale

Activity 4.4: Molecular Models for Ethanol Burning (50 min)

Learning Tracking Tool for Systems and Scale (1 per student)
Assessing the Learning Tracking Tool for Systems and Scale
Questions, Connections, Questions Student Reading Strategy
Using Big Idea Probes
Forms of Energy Cards (1 set pair of students)
Molecular Models 11 x 17 Placemat (1 per pair of students)

Activity 4.5: Explaining Ethanol Burning (40 min)

Three Questions Handout (Color Version)
Three Questions Handout (BW Version)
Questions, Connections, Questions Student Reading Strategy
(Optional) Big Idea Probe: Fill 'Er Up (1 per student)
(Optional) Assessing the Big Idea Probe: Fill 'Er Up
(Optional) Example Systems and Scale Explanations Handout (1 per student or per group)

Activity 5.1: Molecular Modeling for Methane Burning (40 min)

(Optional) Forms of Energy Cards (1 per pair of students)
(Optional) Molecular Models 11 x 17 Placemat (1 per pair of students)

(Optional) Activity 5.2: Explaining Methane Burning (40 min)

Three Questions Handout (Color Version) (1 per student)
Three Questions Handout (BW Version) (1 per student)
(Optional) Example Systems and Scale Explanations Handout (1 per student or per group)

Activity 5.3: Preparing for Future Units – Organic vs. Inorganic (40 min)

Learning Tracking Tool for Systems and Scale (1 per student)
Assessing the Learning Tracking Tool for Systems and Scale

Activity 5.4: Explaining Other Examples of Combustion (50 min)

Three Questions Handout (Color Version) (1 per student)
Three Questions Handout (BW Version) (1 per student)
Learning Tracking Tool for Systems and Scale (1 per student)
Assessing the Learning Tracking Tool for Systems and Scale
(Optional) Big Idea Probe: Fill 'Er Up
(Optional) Assessing the Big Idea Probe: Fill 'Er Up

Activity 5.5: Systems and Scale Unit Posttest (20 min)