Alison's Montessori Materials
Subtraction Strip Board and box containing strips : 1 set
This set includes one hardwood board with 18 numbered squares across the top and 12 squares downward. A wooden box with 9 red and 9 blue wooden strips printed with the numerals 1-9 and 18 natural wooden strips of varying lengths are provided for the exercises. The natural strips indicate the value to subtract from and the blue strips indicate the value to be subtracted.