NumberFit Brain Box - Logic & Counting Puzzle

NumberFit Brain Box is a chunky, colorful 3D puzzle designed to help kids (and adults) stretch their brains while they play. The set is made of numbered blocks (1 to 5) in different shapes that can be packed tightly into the corner box or used to build small towers and patterns on a table. Kids have to rotate, flip, and test different combinations to make everything fit, which really supports spatial awareness, planning, and problem solving.

I designed this with young learners in mind so each piece is big, easy to grab, and nice and bright. The numbers on the blocks can be used for extra activities, such as counting, number matching, ordering, or making “equations” with the shapes they choose to place. It works well at home, in a classroom, or as a calm little fidget puzzle on a desk.

Printing is simple. All parts are flat on the bed and print without supports. You can use one color, but it really shines when you mix several bright colors for the blocks. PLA works great, although PETG should also be fine. You can scale the model up or down and the puzzle will still work as long as all pieces are scaled by the same amount.

If you try it with kids, I would love to hear how they use it in their own creative way.