Subtraction table with rods

The material, completely made of birch wood and with non-toxic paints, consists of:

- a square board engraved with the numbers 1 to 18 at the top. The maximum number is 18 because it is the maximum number that can be combined with the larger red and blue rods: 9+9. The number of vertical boxes is 10 because, in the base 10 system, this is the maximum number of possible combinations. The more marked vertical line at 9 signals to the child the need to first remove the units beyond 10 and then subtract within 10, thus breaking down the subtrahend into two numbers;

- a box without a lid, which contains two sets of rods: nine blue and nine red, both of the same height as the squares and varying in length from 1 to 9 squares;

- a box without lid containing 18 wooden rods.

Handcrafted product made in Italy with certified raw materials.