Grade 2 · Subtraction
Community flowerpots: subtract from a larger collection
At a community garden, 126 flowerpots are available and 12 are taken away. Change the controls and explain what the animation reveals.
Predict what will happen, press Play, then pause and explain what changed. Every control also works without playback.
Watch the relationship
PausedHD animation studio
From experiment to screen.
Present a crisp Canvas scene, save a full-HD image, or capture your model as a silent video.
Understand what you are seeing
The idea behind the motion.
At a community garden, 126 flowerpots are available and 12 are taken away. Subtraction separates an original whole into the removed part and the remaining part. The remaining quantity must be counted after the removal, not by recounting the crossed-out objects. At the end, 114 remain. Adding back the removed 12 reconstructs the original 126.
A relationship to keep
126 − 12 = 114
Read the symbols alongside the explanation. A diagram shows the relationship; the assumptions tell you when it applies.
- STEP 1
Read the starting situation
At a community garden, 126 flowerpots are available and 12 are taken away. Identify what each number measures before changing a control; the worked example refers to these starting values.
- STEP 2
Follow the mathematical change
Move the timeline to increase the removed amount. The pale or crossed-out section records what has left; the colored section records what remains. Pause on an intermediate frame and compare the picture with the live readouts.
- STEP 3
Explain and test the relationship
At the end, 114 remain. Adding back the removed 12 reconstructs the original 126. Change one input, predict its effect, and test whether the same relationship still works.
Your turn to explain
Make a prediction. Test your reasoning.
Community flowerpots: use the original situation. At a community garden, 126 flowerpots are available and 12 are taken away. Return one removed object when possible. What remains then?
Use the values specified in the question. Reset restores the initial values for this investigation.
Compare your explanation
115 remain: 126 − (12 − 1) = 115.
Work through a full lesson
Connect the animation to a worked example and practice questions.