Tips for Geometry
Geometry includes the study of angles, triangles as well as the study of perimeter, area and volume. Knowlege of geometry is absolutely necessary for everyone. The actual word geometry means earth measure.
Following is a collection of geometry ideas that could be adapted for use in elementary classrooms.
Precut construction paper rectangles, squares, circles, trapezoids, etc. Pretend you are a spider sitting on the ceiling. Create a map of your classroom using the precut shapes. Add details.
Cut one side off a cardboard shoe box. Cut two hand-holes on the opposite side. Place an assortment of shapes inside the box. Person A inserts his hands into the box and tries to find two matching shapes. Person B verifies his choice, etc.
Students can classify and sort three-dimensional shapes according to various attributes. Test to see which roll, slide or both.
In groups of two, three or four and using 6-8 m of yarn, work together to make a square, rectangle, triangle, hexagon, pentagon, etc. How many corners will your shape have? How many sides? Will the sides be different sizes? Will the edges be straight or curved. Can you find similar shape objects in the room, school-yard, etc.?
Using geometric shape models, reproduce these using toothpicks and marshmallows (or carrot slices, frozen peas, plasticine, etc.)
Variation: Create your own structures.
Make two equilateral triangles using five toothpicks. Make five triangles, using nine toothpicks, then take away three toothpicks to leave one triangle. Make four squares using twelve toothpicks.
Go on a shape walk. Record the shapes you observe and where you find them.
Variation: Divide the class into groups. Give each group one shape and have them record things that have the shapes they are carrying.
Children can create a geometry shape such as a square (Shape A) on the geoboard, then change Shape A into Shape B (a triangle shape) noting necessary movements and changes.
Using attribute blocks, make a one-way change train. Each shape differs from the previous one in only one attribute.
Variation: Make two-way or three-way change trains.
Use a tracer shape set and draw the various shapes. Fold the paper shapes to determine the various lines of symmetry. How many lines of symmetry does each shape have?
Give each child a half-sheet of clean paper. Challenge children to cover complete area using pattern blocks.
Variation: match congruent (same size, same shape) two-dimensional figures using pattern blocks.
Play "Chain Game" using attribute blocks. Person A puts down a piece. Person B joins a piece which is different in only two ways, etc. Game over when one player uses all his/her shapes or no one can use a piece.
Place a ruler on the floor. Pretend this line is a mirror. Person A places a geoshape so that one edge touches the mirror line. Person B places his/her matching piece to make a mirror image.
Fold paper to make shapes. Fold a square to make a rectangle; fold a rectangle to make a triangle; fold a rectangle to make a trapezoid; fold a trapezoid to make a diamond.