With each practice unit, the children earn puzzle pieces from now on, which come together to form a fun picture at the end. The proven clear structure and child-friendly layout ensure that the children practice and repeat the arithmetic content of the respective school year independently and with a lot of fun. New are the solution pages inserted in the middle section, with the help of which the children can check their solutions themselves. (If such self-checking is not desired, the middle section can simply be removed). The exercise books can be used independently of the textbook used. With each exercise unit, the children earn puzzle pieces that come together to form a fun picture at the end. The proven clear structure and the child-friendly layout ensure that the children themselves grasp the arithmetic content of the respective school year.