National Council of Teachers of Mathematics
The Math Forum: Defining Geometric Figures
This site provides an in-depth definition of a two-dimensional figure and a three-dimensional figure. Related terms include arcs, vertices, polygon, and many more.
Illustrative Mathematics
Illustrative Mathematics: G Gmd, G Mg Tennis Balls in a Can
In this task, students investigate the volume of tennis balls and their cylindrical container, the empty space around the balls, different ways of slicing them, and what their visualizations will look like. Aligns with G-GMD.B.4 and...
Purple Math
Purplemath: Geometry Word Problems: Introduction
Introduces how to set up and solve simple geometric-figure word problems. Includes advice regarding formulas to memorize.