So we are always looking for ways to get kids interested in math and science. What could be better that doing that and teaching them practical life lessons. I originally found this site because it has a cool conversion calculator over at the Science of Cooking site. If you further explore the site, there are cool kitchen lab experiments. They even break down the structure of the Maillard Reaction and how to make salt sculptures. Even in the most basic issues, they deal with both the practical and the scientific. One example of this is their answer to why hardboiled eggs have the green ring and how to avoid getting it. So get your kids in the kitchen doing math, science and eating!
The digital books can be found on a much wider range of issues that traditional books. This is because it is much easier to get an e-book available to the public than a traditional book. The latter consists of an editor and if you want to cover a larger area, has to be a major publisher. The costs involved with traditional books are also higher.