A wooden tray contains 4 boxes with lids:
The purposes of this material:
- 5 bars of each colored bead bars 1-9;
- 5 bars of each of the grey bead bars 1-9;
- black and white bead stairs 1-9;
- 23 golden bead bards of 10.
N Beads are 8 mm plastic, wired by copper
- Introduces the child to the unit combination of subtraction.
- Teaches how to subtract concrete representation of negative functions.
- Preparation for algebra (equal quantities of opposite sign eliminate each other).