Grade 3 · Addition
Festival lanterns: combine hundreds and regroup the total
At a neighborhood festival, a first group contains 200 lanterns and another group brings 45 lanterns. 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 neighborhood festival, a first group contains 200 lanterns and another group brings 45 lanterns. Addition joins two disjoint groups. Keep the starting group in the count while the second group arrives; the result includes every object from both groups. The final 245 can be checked by removing the 45 arrivals and recovering 200. For larger totals the bars summarize quantities rather than drawing every object.
A relationship to keep
200 + 45 = 245
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 neighborhood festival, a first group contains 200 lanterns and another group brings 45 lanterns. Identify what each number measures before changing a control; the worked example refers to these starting values.
- STEP 2
Follow the mathematical change
Scrub from no arrivals to all arrivals. The current total grows by the number of objects that have joined so far. Pause on an intermediate frame and compare the picture with the live readouts.
- STEP 3
Explain and test the relationship
The final 245 can be checked by removing the 45 arrivals and recovering 200. For larger totals the bars summarize quantities rather than drawing every object. Change one input, predict its effect, and test whether the same relationship still works.
Your turn to explain
Make a prediction. Test your reasoning.
Festival lanterns: use the original situation. At a neighborhood festival, a first group contains 200 lanterns and another group brings 45 lanterns. If one extra object joins the second group, what is the final total?
Use the values specified in the question. Reset restores the initial values for this investigation.
Compare your explanation
200 + (45 + 1) = 246. One additional arrival increases the total by one.
Work through a full lesson
Connect the animation to a worked example and practice questions.