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Systems and Scale Read Me Document

Carbon TIME Systems & Scale Unit: Read Me Document


The Systems and Scale Unit is a tool kit, not a script.

While the Systems and Scale Unit Teachers’ Guide may look like a script with lots of activities to do one after another, it is actually designed to be more like a user’s manual for a set of tools. You can decide which tools are right for your students and your goals. This document alerts you to choices to make before each lesson.

Making Your Choices

Here is a brief summary of choices for teaching Systems and Scale. See the Teacher’s Guides for more in depth discussions of your choices.

Lesson 1

All students should complete Lesson 1.

Lesson 2: Choose whether or not to teach Activity 2.2.

The activities in Lesson 2 are important and foundational for the Carbon TIME curriculum. Depending on the academic level of your students, you may not need to teach Activity 2.2. It is a tactile opportunity for students to continue exploring scale. Use your professional judgement about the best choice for your students.

Lesson 3: Choose whether or not to teach Lesson 3.

We have found that for students who have not previously studied chemistry or chemical change, the relatively complicated chemical change in Lesson 4 (burning ethanol) is a heavy load. Lesson 3 is an optional opportunity to engage your students in the Carbon TIME activity structures (using investigations, molecular modeling, and chemical equations to explain chemical changes) while focusing on the simpler chemical change of soda water fizzing. Use your professional judgement to decide whether or not to teach this lesson.

Lesson 4: Choose how to use scaffolds in Activity 4.5.

There are a set of scaffolding tools you can choose to use with your students in Activity 4.5, including example explanations, the Three Questions Explanation Checklist, a reading, and a graphic organizer. You may find that you use more of these scaffolds early on and gradually use fewer over time depending on your students’ needs. Use your professional judgement about the best choice for your students

Lesson 5: Choose whether to use embedded activities for additional scaffolding.

There are three main choices to make about activities in this lesson:

  • Activity 5.1 is optional. Students will use molecular models to model the chemical change which occurs when methane burns. Your students may not need to do this depending on their performance in Activity 4.4 using molecular models with ethanol burning.
  • Activity 5.2 is also optional, and you should consider whether your students can already explain what happens to matter and energy when methane burns at an atomic-molecular scale. If so, you may choose to modify or skip Activity 5.2.
  • Activity 5.4 engages students in reading about three different fuels and explaining their combustion. You probably don’t want every student to do a worksheet on all three fuels, so there are several ways that students could become “experts” on one fuel, then compare what they have learned: a jigsaw activity, working in groups to make posters, etc. You may choose to scaffold the explanation writing on the worksheets using the Three Questions Explanation Checklist, as in Activity 4.5.

Key to text colors:

  • Black Text Activities for All Students
  • Blue Text Optional Activities (Omit if students are already proficient)

Read Me Unit Outline