Divide the class into groups of five. Draw a number of shapes on the board, such as a circle, an isosceles and a scalene triangle, a rectangle and a cube. Give teams two minutes to think of as many real-life objects resembling those shapes as possible. Students are allowed to cooperate with their teammates during those two minutes. The team to come up with the most correct objects is the winner.
Prepare a list of shapes you want students to recover. Make a copy for each student and distribute it in class. Instruct students to bring you objects resembling the geometric shapes mentioned in the list. They can use their personal objects, objects found in the classroom or objects found within the school in general. The hunt must take place during recess, so that students can freely search the whole school for objects. The student to find all -- or most -- of the listed items is the winner.
Stand in the corner of the classroom, so that you can see all students. Instruct students that on every round, you will list the attributes of a geometric shape and you need them to raise their hand when they have figured out which shape it is. Start each round with the phrase "I want a shape" and continue with the attributes: "that has equal sides and three corners." The first student to raise his hand gets to give an answer. If he is correct, he earns a point. If he is wrong, he loses one. The winner is the student with the highest score at the end of the game.
Create drawings of animals, buildings or objects, using only geometric shapes. For example, when drawing a cat, use a circle for its head, two isosceles triangles for ears, circles for the eyes, a rectangle for the mouth, two isosceles triangles for the teeth and six rectangles for the body, feet and tail. Ask children to work separately and try to identify all geometric shapes within your drawings. The first student to identify all shapes correctly is the winner.