Blogs » Learning in Freedom » Confessions and a few COOL Math Links

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I don’t know if I’ve confessed to you that I take a “better late than early” approach to schooling here in my home. If you Google that phrase you will find a book with that title. I don’t feel comfortable discussing delayed formal academics on a local forum, especially when “unschooling” and “radical unschooling” have received so much negative attention. I fear these concepts are misunderstood. Delaying formal academics looks very much like unschooling.

Last week I decided to buckle down and begin some formal learning with my nine year old. Obviously, it involved some catching up, but not as much as one might expect. That fact always blows me away.

The only hindrance to doing grade level math was that my son didn't have his multiplication tables memorized. I've observed that what he lacks in memorization he has made up for by thinking about numbers and their relationships. He is able to rearrange numbers and stack them back up to get to a solution. For example, “Six times eight is three sixteens and three sixteens is the same as thirty and three sixes.” This is how he thinks when he comes to a little fact that he doesn’t have memorized.

Today, as my son was working out some math problems, I reminded him about the trick to multiplying a number by nine. Do you remember the little trick? If you are multiplying any one-digit number by nine, the answer is going to be one less than that number followed by whatever will add up to nine. The answer to nine times eight will start with a seven followed by a two…

As he was working on his math, he discovered another trick with nines. He told me that if you would take the number you are multiplying by nine, stick a zero on the end of it, and then subtract the number from the new number, you have your answer. “Nine times eight is eighty subtract eight.” My daughter tested this and it worked past the one-digit numbers.

It was new to me, which is why I'm sharing it, but apparently, it’s not a new trick: Multiplication Tips

Check out this site: Free online physics, chemistry, biology, earth science and math simulations.

Also, if you love math, music, art and their relationship, check out Vi Hart's Blog. Here is a video from that site: