Our self-checking, interactive Subtraction Practice Board provides independent, tactile subtraction practice for facts up to 17-9. Students solve each subtraction problem and then spin the dial to check their answers. When they're done, they simply raise the handles on the sides to reset the dials and practice again! Students will enjoy solving 81 subtraction problems using this self-checking Subtraction Practice Board. This interactive board provides independent, tactile practise for subtraction facts all the way up to 17 – 9. Students solve each subtraction problem and then spin the dial to check their answers. When they’ve completed the board, they raise the handles on the sides to reset the dials so they can begin again. It is ideal for self-directed learning in the classroom or at home. Also available is an Addition Practice Board, which is sold separately.