- Definition
A prism is a 3D shape, like a box or a Toblerone bar, that has two identical ends (called bases) that are connected by flat sides. We name the prism by the shape of its ends, so a box is a rectangular prism and a Toblerone is a triangular prism.
A box of cereal is a rectangular prism because its top and bottom are matching rectangles.
How to teach this in 30 seconds
Try this analogy: A prism is like a building block that has the same flat shape on both ends.
Ask your child: Can you find a box with the same shape on both ends?
Common mix-up: Kids may think any 3D shape with flat sides is a prism. The key is that a prism must have two matching flat ends, like a top and a bottom.
Examples
- A Toblerone box is a triangular prism because it has a triangle on each end.
- A building block with a square on each end is a square prism.
prism is a term used in Ontario’s Kindergarten to Grade 8 curriculum.
Where this shows up
The descriptions on this page are SmartStudy’s own original, plain-language writing — not the Ministry’s wording. They are aligned to the Ontario Curriculum, © King’s Printer for Ontario. For the Ministry’s official wording, see the source link below. SmartStudy is an independent service and is not affiliated with, endorsed by, or sponsored by the Government of Ontario or the Ministry of Education. Ontario Curriculum and Resources ↗
