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The Counting Box

You know how Everett loves the calculator, especially to simply count? Four months ago I set out to make him something better than a promotional giveaway calculator: a dedicated counting box. It would have big buttons and be easy to use, look good, and most importantly it would remember where you left off so you could keep counting later. I finished it in time for his birthday last weekend.

The box is laser cut from bamboo, and I designed the circuit myself. Use the dial in the middle to choose the number from 1-10 that you want to work with, then push the green button to add that number or the red button to subtract it. The LED display is visible in the dark and can count to 99,999,999. That should keep him busy a few weeks, right? To save batteries, it turns itself off after a minute without use.

At the back is a removable door that allows access to the USB charging port and lets you see the circuit. A plexiglass cover keeps prying fingers away from fragile wires.

Needless to say, he loves it. It’s been fun to watch him build an understanding about numbers and their relationship with each other as he figures out the best way to reach a number he wants. 10 and 6 is 16, but so is 8 and 8, and you don’t have to switch the knob!

Click here for the full nerdy write-up of all the details.

Posted in Craft.

2 Responses

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  1. G.A. Sally says

    What a neat invention, Nathan. I’m sure I’m not the only one thinking that you should get a patent and see if a company would start making them. Sal

  2. Geri Cordova says

    Amazing, Nathan! The teacher in me is amazed at the possibilities for this. Patent and advertise!!!! And once again I’ll say that Everett is SO lucky he has you and Sara for parents, and yes, Erin as an uncle!



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