Three-dimensional Learning Progression In this final lesson of the unit, students have completed the inquiry and explanation sequences for decomposers’ growth and movement. The activities in the previous lessons were designed to walk students through a cognitive apprenticeship model of Establishing the Problem, Modeling, Coaching, and Fading. The results of the unit posttest will help you determine if your students are ready to move on to other units and carry forward concepts from this unit into those future units. If the results from your posttest imply that a majority of your students are still struggling with certain concepts, it might be valuable to return to some of the main concepts they are struggling with before moving on to the next Carbon TIME unit. Key Ideas and Practices for Each Activity Activity 6.1 is an optional activity that allows students to explore other types of decomposers through activities, readings, and videos. The 6.1 Decomposers Without Oxygen Reading and Modeling Handout is the only activity in the Decomposers unit that addresses anaerobic conditions which is a component of HS-LS2-3. Activity 6.2 is the Fading phase of the Explanation Activity Sequence, which provides students with important less-scaffolded practice with digestion, biosynthesis, and cellular respiration. Students should take more responsibility for their work than in Lessons 4 and 5, which included the Modeling and Coaching phases. Students answer the Three Questions for different decomposers growing and moving using the Explanations Tools, coordinating accounts at the macroscopic and atomic-molecular scales. Macroscopic scale accounts include these components: the structure of the system (the decomposer in this case) and the movement of materials through the system; the location where chemical changes take place (outside and inside decomposers’ cells); the materials involved in the chemical changes: the reactants going in and the products coming out. Atomic-molecular scale accounts include three different ways of representing chemical change: molecular models, with twist ties to represent units of energy, that students use to physically rearrange the atoms of the reactant molecules into the molecules of the products; a chemical equation that shows how atoms are rearranged into new molecules in a compact way (but does not account for energy); the Explanations Tools, which provide a way for students to account for changes in matter and energy in writing by answering the Three Questions. In Activity 6.3, which is also part of the Fading phase of the Explanation Activity Sequence, students think across the macroscopic-focused Carbon TIME units to compare how decomposers grow and function with how animals and plants grow and function. In Activity 6.4, the final component of the Fading phase of the Explanation Activity Sequence, students write generalized explanations of how all decomposers grow, move, and function with reduced scaffolding. Activity 6.5 includes summative assessment for the unit. You can track students’ progress by having them take the unit posttest (identical to the unit pretest) and comparing the results of the two assessments. Key Carbon-Transforming Processes: Digestion, Biosynthesis, and Cellular Respiration Content Boundaries and Extensions
