Geometric Solids: 2D vs. 3D

In kindergarten, students learn to identify if a shape or figure is 2D or 3D, “flat” or “solid.” A picture of something will always be flat, but the actual object would be something a child could hold. Solid figures have mass and take up space, while flat figures do not. Show examples of solid figures and paper cut-outs of two-dimensional shapes and have students classify them. Then show solid figures and pictures of solid figures and lead students in a brief discussion on the difference. Many students will already understand the difference between 2D and 3D, but they will have a hard time grasping the “D” part and what it means.

In this activity, students will identify different dimensions and provide examples of where they appear in real life. This will provide them with a better understanding of geometric solids. Introduce the terms shape, plane, solid, and space. Depending on the level of your students, particularly if this is a review for older students, you may also want to add point, line, dimension, and perspective.

The example storyboard can also be modified and used as a teaching visual, printed out as a "cheat sheet" for students to keep in their notebooks, or used as inspiration for a worksheet where students must define and draw the symbols for each term.