Here’s a nice book for you to share with children: The Pig and the Box. It’s licensed under the Creative Commons NonCommercial ShareAlike license so you can share it non-commercially as much as you like. You can even build on it, remix it, translate it, and make new stuff based on it so long as you license your new stuff under the same license. If you don’t like any part of it you can change it and republish it non-commercially.
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