Plants Lesson 1 Background Information

Three-dimensional Learning Progression

The pretest and discussion in this lesson (a) help students to anticipate and begin thinking about the questions that they will answer in this lesson and (b) help you as a teacher see how your students reason about matter, energy and the carbon-transforming processes of photosynthesis, cellular respiration, and biosynthesis. In the Application activity Sequence, both Activity 1.1 and Activity 1.2 in this lesson serve as the “Establish the Problem” phase for all the activities in the Plants Unit.

Key Ideas and Practices for Each Activity

In Activity 1.1, the unit pretest is useful for two purposes. Your students’ responses will help you decide how much detail you want to include during the unit, particularly details about chemical structures of materials. If your students are mostly at Level 2 in the carbon learning progression, you may want to focus on the main ideas (like the tracing of matter and energy and the Three Questions) rather than chemical structures. Your students’ responses will also provide a starting point for discussions about the focus for this unit.

In Activity 1.2, through the discussion students will come to recognize that they have many different ideas about what how they think plants grow, as well as unanswered questions. We expect many students to express Level 2 or Level 3 ideas, for example, that plants grow because soil minerals coming into the plant through the roots provide energy for plant growth. Though most students will know that plants need light and that light is absorbed by the leaves, even students who know the word “photosynthesis” are likely to be vague about what happens during photosynthesis, particularly that photosynthesis enables plants to use CO2 as a carbon source for storing chemical energy and building plant tissues.

Key Carbon-Transforming Processes: Photosynthesis, Cellular Respiration, & Biosynthesis

Content Boundaries and Extensions