OpenSciEd Unit 7.4 · Lesson 11 · 11.A
Look for: Student predictions demonstrate whether they…
MS-LS1-5MS-LS2-3Assessment opportunity · Formative assessment
From Teacher Edition
Facilitation guidance from the lesson plan — what to notice in student thinking and how to respond while teaching.
Building towards
11.A Plan and carry out an investigation collecting data of relative concentration of carbon dioxide changes over time in different closed systems to answer the question, Why don’t plants die when they can’t do photosynthesis?
What to look / listen for
- Student predictions demonstrate whether they believe plants are doing cellular respiration and understand what should be happening in each bag.
- Students can properly identify that BTB will change from a dark blue-green color to a yellow-brown color in the presence of CO2, and that color change is dependent on the amount of CO2 present.
- The bag with exhaled air (bag B) should show a change because it contains carbon dioxide, and bag A should show little to no change.
- Students can collect descriptive and accurate data.
What to do
If students don’t remember what color BTB changes to in the presence of CO2, perform a demonstration by exhaling through a straw in the BTB solution.