The clock is driven by the ubiquitous 28BYJ-48 stepper motors that can be found on eBay for a few bucks. They don’t have much torque, but all they have to do here is turn a cardboard disk.

The clock starts off with fairly easy equations, and then can get gradually more difficult to solve as a child’s math skills get better.

Raspberry Pi enthusiasts looking for a new project to keep them busy this weekend may be interested in this awesome Raspberry Pi seven segment analogue clock, powered by the Raspberry Pi 2 model B ...

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