Examine the shape to see whether it is two-dimensional or one-dimensional. Check to see whether the shape looks flat or like it is popping out of the page. Teach your students to use different criteria to name 2-D and 3-D shapes.
Count the sides of the shape to identify the basic geometric classification. This method is often the most effective for identifying two-dimensional shapes. For example, a 2-D shape with three sides is a triangle. A shape with four sides is a quadrilateral.
Note additional characteristics of the shape like side length and angles to pinpoint its identity. For example, if the shape has two congruent pairs of sides that are not the same length and four right angles, it is a rectangle.
Count corners and compound shapes to identify three-dimensional shapes. The differences between two-dimensional shapes within 3-D geometric figures is often enough to identify the shape. For example, a three-dimensional shape with two circles on the top and bottom and no corners is a cylinder, while a shape with one circle on the bottom and a point on the top is a cone.
Round out your students’ knowledge of geometric shapes by encouraging them to show examples of shapes in the world around them. Encourage them to identify shapes of household or classroom items like books, pencils and wall clocks. Practicing identifying shapes by showing them is a great way to solidify each student’s knowledge and understanding of the basic shapes.