Kubiya Games Puzzle of the Month

What's in the box: Each box holds one to three handcrafted mechanical puzzles, such as wooden interlocking, metal disentanglement or burr puzzles, plus an illustrated solution guide you open with a QR code.

Kubiya Games runs a mechanical puzzle subscription shipped from its Brooklyn studio. It comes in three levels: Player for beginners, Explorer for intermediate solvers and Thinker for experienced ones. Puzzle types include wooden interlocking puzzles, metal trick-opening and disentanglement puzzles, brass sequential discovery puzzles and Japanese burr puzzles. Each comes with an illustrated solution guide you open with a QR code. Every tier costs $39.99 a month when you prepay three months ($119.97). Single boxes cost $45.99, $54.99 or $57.99 depending on level, and 6 and 12 month plans save more. Plans are prepaid with no automatic renewals, which is a nice change from boxes that bill until you cancel. Shipping within the US is free. If you are shopping for math and logic kits for children, know that this is not really a kids' product. The site markets it to curious minds of any age and gives no age range, so parents will need to judge whether a child is ready, especially for the harder levels. It is also unclear how many puzzles you get: the plan cards say 1 to 2 per box, but the sample boxes show two or three. Mechanical puzzles are good for building patience and spatial reasoning, but there are no lessons or worksheets. This is a box for play more than teaching.