Geoboard, double sided, yellow. On one side features 121 of studs (11 × 11) to layout squares, using tires, and make all geometric shapes to understand symmetry etc.
On the other side has stunds again but each line is symmetric with the second rather than the next (isosceles triangle layout) For example, row 1 is symmetric with the 3 ,5, 7, etc.
The nails are 11x10x11x10x11 … etc.On this side of the geoboard we make geometric solids in level.one side 11×11
other side 11x10x11x10.. (11×7, 10×6)