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The Carbon TIME (CTIME) project is a collaboration of scientists, teachers, graduate students, and IT specialists with the overall arching goal to refine current K-12 frameworks and assessments for learning progressions that lead to environmental science literacy. Given the above, we have developed a series of six teaching modules that can be used at the middle school or high school level. Each of these learning modules are nested within this website along with assessments for each learning module.

Systems and Scale View Unit
AnimalsView Unit
PlantsView Unit
DecomposersView Unit
EcosystemsView Unit
Human Energy SystemsView Unit
1. Foundational Unit 3. Organism Scale Units 2. Large Scale Units

Systems and Scale

The Foundational unit (Systems & Scale) is taught first in every Carbon TIME unit sequence, no matter which other units you are teaching. It can also be revisited in following years if students are struggling with basic principles of matter and energy. In this unit, students trace matter and energy through a flame when ethanol burns, building foundational concepts and practices. The Carbon-transforming process addressed in this unit is combustion.

Scale Units

The Organism Scale units (Animals, Plants, and Decomposers) engage students in tracing matter and energy through organisms (e.g., mealworms, lettuce plants, and bread mold). These units address the same big ideas in different contexts, focusing on the processes within an individual organism. The Carbon-transforming processes addressed in these units are photosynthesis, cellular respiration, digestion, and biosynthesis.

Scale Units

The Large Scale units (Ecosystems, Human Energy Systems) engage students in tracing matter and energy through larger systems. At the large scale, students trace matter through carbon pools (e.g., producers, consumers, atmosphere) instead of through single organisms. These units focus on all five carbon-transforming processes.