Put shapes together to make new shapes
Fitting shapes together is playful work that builds your child's spatial reasoning, the skill of moving shapes around in their mind, which helps with puzzles, building, and reading maps. It also sets up later math: two half-circles making a whole leads into fractions, and covering a rectangle with small squares leads to area in 3rd grade.
In this video, your child will learn to put shapes together to make new shapes.
The lesson stops at each question for your child's answer.
Three problems, each a little harder
Each problem is worked step by step. Your child will solve the last one before Bobby shows how.
Example 1
What shape do two cubes make?
Example 2
How many triangles make the rectangle?
Your child's turn
How many sides does the new shape have?
The three key steps
- 1Join shapes with full sides or faces touching.
- 2A new shape can join others too.
- 3Count the pieces that make the whole.
Mistakes to listen for
- Overlapping shapes or leaving gaps between them, then being unsure what new shape has been made.
- Missing a familiar shape once it is built from smaller pieces, like not seeing that two triangles make a square.
- Naming a combined shape after its pieces, calling a rectangle made of two squares "two squares."
The lesson shows every step, so your child sees why it works. Read our parent's guide to building bigger shapes from smaller ones →
Is your child ready to practice what they've learned?
Bobby's Math Club offers unlimited practice for free.
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More 1st grade Geometry, with questions your child answers along the way.
Questions parents ask
Does my child need an account to watch?
No. You can watch this on any device at any time. If your child would like to practice building bigger shapes from smaller ones, and you'd like parent-friendly reports on your child's progress and growth, you can join Bobby's Math Club for unlimited free practice.
What happens when my child answers a question?
A right answer gets a cheer, and the lesson carries on. If your child isn't sure, they can tap "I don't know yet", and Bobby gives the answer and shows another example. Nothing is scored or stored.
Is this the same lesson that's on YouTube?
Yes. Here, the lesson stops at each question and waits for your child to answer. On YouTube, each question stays on screen for a few seconds, and then the lesson plays on.
Where can I learn more?
There's a short, kid-friendly lesson like this one for every Pre-K to 5th grade math skill, all in our video library. Our parent's guide to building bigger shapes from smaller ones has more on where kids get stuck and how you can help at home. In the club, your child practices at just the right level, about five minutes a day, and you get parent-friendly reports as they grow. Learn more about how it works →
Practice building bigger shapes from smaller ones
Questions at your child's level, about five minutes a day, on building bigger shapes from smaller ones and whatever PK-5 skills they need to develop. Unlimited practice, free forever.
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