What is a Rectangular Prism (Cuboid)?
A rectangular solid shape with opposite faces equal in size
A rectangular prism or cuboid is a three-dimensional (3-D) solid shape with six rectangular faces. Every corner of a rectangular prism is at a right angle (90°), and opposite faces are equal in size.
How can we tell if a shape is a rectangular prism? Check for these properties:
- It has 6 faces, all shaped like rectangles.
- It has 12 edges (the lines where faces meet).
- It has 8 vertices (corners).
Rectangular prisms are all around us! Some examples you may encounter today are:
- A shoebox
- A brick
- A book
We can measure properties of rectangular prisms, such as:
- Volume – how much space it takes up
- Surface area – the total area of its six faces
When Do Students Learn About Rectangular Prisms?
Students are typically introduced to rectangular prisms or cuboids when they study 3-D shapes and measurement in elementary school.
Grades 2–3 – Recognizing Rectangular Prisms
Students learn to identify rectangular prisms and compare them to cubes and other 3-D shapes.
Grades 4–5 – Measuring Rectangular Prisms
Students learn how to calculate the volume and surface area of rectangular prisms and apply these concepts to real-world problems.
