“Mystery Number Challenge” is an excerpt from Let’s Play Math: How Families Can Learn Math Together—and Enjoy It, which is available as an ebook at my publisher’s store (where you get all formats for one low price, and I earn higher no-middleman royalties) or through other online retailers, or by special request through your local library. Read more about my playful math books here.
The Math Game Monday posts will be available for one week only. If you missed this one, explore the links in the sidebar. There are more than forty free games scattered around the blog. Have fun playing math with your kids!