OpenSciEd Unit 6.3 · Lesson 11 · 11.B
Look for: a force of gravity arrow pointing downward
From Teacher Edition
Facilitation guidance from the lesson plan — what to notice in student thinking and how to respond while teaching.
Building towards
11.B Develop a model to represent balanced and unbalanced forces on an object suspended by an upward current of air, and use the model to predict and explain whether the object would remain suspended (stability) or start moving downward or upward (change) due to the relative strength of the opposing forces.
What to look / listen for
The following elements should be visible in student models for Case C:
a force of gravity arrow pointing downward
a lift force arrow pointing upward
a smaller lift force arrow than the gravity arrow
a movement arrow pointing downward and/or a description that the object will begin to fall (or sink)
What to do
If some students’ models are missing any of those key elements, bring the class back together and work through the four elements together, asking what the reason is for including each one.