This guided geometry lesson takes second graders on an exploration of 2D and 3D shapes. Kids will learn how to sort shapes, as well as partition them into halves, quarters and thirds. Tangrams are also featured within the exercise in order to give kids practical ways of practicing their new geometry skills. For more printable practice, try the geometry worksheets recommended by our curriculum advisors to accompany this lesson.
Explore 3-D shapes with your students and help them identify and talk about the relevant attributes of three-dimensional shapes, all while using real-world examples! Use this as a stand-alone lesson or alongside the Shape Models lesson.
Help students understand edges and vertices with worksheets that explain how to measure the sides of a triangle or calculate the shape’s total area. Vertices may seem complex, but you can give your hands-on learners simple connector sets to help them connect the dots, or give worksheets to color in for those who understood the concept in its abstract form.
Once students learn the attributes of two dimensional shapes, they will be ready to understand that we live in a three dimensional world. The two dimensional or flat shapes have length and width. Once we add in depth, those two dimensional shapes represent a single side of a three dimensional shape.
Three dimensional shapes are made up of three parts: faces, edges, and vertices. The face of a three dimensional shape is a single two dimensional shape that represent any of the individual surfaces of the solid object. An edge is any line that joins two vertices and where any two faces meet. A vertex is any point where two or more lines meet. On a two dimensional object, this is where two lines meet. On a three dimensional object, a vertex is the meeting point of three lines. A vertex can also be known as a corner.
Among the three dimensional shapes, there are a subset of shapes known as platonic solids. These shapes are special because they are made up of congruent regular polygonal faces. This means that all the sides are the same shape and size with identical angles and sides. There are five platonic solids:
Tetrahedron - The tetrahedron has 4 triangular faces.
Cube - The cube has 6 square faces.
Octahedron - An octahedron has 8 triangular faces.
Dodecahedron - The dodecahedron has 12 pentagonal sides.
Icosahedron - The icosahedron has 20 triangular sides.
Working with the resources provided by Education.com above may help students gain a geometrical understanding of three dimensional shapes and how they differ and relate to two dimensional shapes.