Activities and answers ball. These colorful 24'' inflatable vinyl balls provide an excellent way for children to build their learning skills. Each ball features a variety of graphics, problems, facts, and questions to reinforce learning in a fun way. Students will not mind practicing math, language, history, geography, etc. while they can play ball. Basic play involves 2 or more players who toss the ball to each other and answer the question found under their left thumb. Directions and variations on play are included in each CLEVERCATCH, along with a Question & Answer sheet. Pencil and paper may be required for mathematics.