Building Students' Understanding of Energy in High School Biology

Co-Principal Investigator: Stark, Louisa

Project researchers developed and tested a new approach for helping students build connections between macroscopic and molecular energy concepts in the physical and life sciences, while integrating learning across disciplinary core ideas, scientific practices, and crosscutting concepts.

Developers also designed a set of multiple-choice and constructed response items to measure students' understanding of the unit's learning goals. The items were used in pre-and post-tests in (a) a randomized control trial (RCT) that compared the performance of students who used the MEGA unit with that of students' who used their district curriculum and in (b) a field test of the further revised unit that compared the performance of students who had completed the unit to the performance of university biology students.

• The team found that it is possible to design a coherent unit that both targets appropriate NGSS physical and life science core ideas about matter and energy, crosscutting concepts of energy and matter and systems and system models, and science practices of data analysis, modeling and explanation and engages students in making sense of interesting macroscopic phenomena related to the growth and activity of living organisms in terms of underlying molecular mechanisms.
• Students using the MEGA unit in the RCT study outperformed students who used the school district curriculum (Herrmann-Abell et al., 2019).

Student materials consist of 14 lessons that target the following NGSS Performance Expectations:

• Plan and conduct an investigation to provide evidence that feedback mechanisms maintain homeostasis. (HS-LS1-3)
• Develop and use a model to illustrate the hierarchical organization of interacting systems provide specific functions within multicellular organisms. (HS-LS1-2)
• Construct and revise an explanation based on evidence for how carbon, hydrogen, and oxygen from sugar molecules (glucose) may combine with other elements to form amino acids and/or other large carbon-based molecules (growth). (HS-LS1-6)
• Use a model to illustrate how photosynthesis transforms light energy into stored chemical energy. (HS-LS1-5)
• Use a model to illustrate that cellular respiration is a chemical process whereby the bonds of food molecules and oxygen molecules are broken and the bonds in new compounds are formed resulting in a net transfer of energy. (HS-LS1-7)
• 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. (HS-PS1-4)

Carefully sequenced questions throughout the unit's activities guide students in (a) observing phenomena and data involving changes in matter and energy, (b) using models to make sense of matter changes during chemical in terms of atom rearrangement and conservation, energy changes during chemical reactions in terms of bond breaking and bond forming, and energy transfer in terms of coupling energy requiring to energy releasing systems, (c) connecting observations of phenomena and models to science ideas, and (d) explaining related phenomena using evidence, science ideas, and models.

The teacher materials provide information about the purpose and intent of the unit and of each lesson and activity, including information on the core ideas and practices that are targeted and the instructional strategies that are embedded in each lesson. In addition, the teacher materials identify common student learning difficulties and provide examples of correct responses to all questions and tasks students are expected to complete.