Clever Catch Trigonometry ball is a subject that all students need extra review with. These colorful 24" inflatable vinyl balls provide an excellent way for children to build their math skills. This Clever Catch ball will be a great addition to the 8-12 classroom. Sides and angles of planes or spherical triangles and the calculations based on them, are covered in the questions. Toss it around the room and see what happens. All answers are provided on the enclosed answer sheet. Trigonometry Clever Catch provides an excellent way for students to challenge themselves while learning. Clever Catch can be used at school in organized classroom activities. It can also be used at home. For grades 8 to 12. include repair patch, no latex.