One of the greatest carschooling resources is the Guinness Book of World Records. It has many practical uses for math in it that help kids see how math is used in the real world. It includes statistics, facts, and figures on the greatest speed achieved by a human being; circumnavigations by balloonists, ships, and airplanes; the highest mountain; the deepest ocean; survival records; the biggest galaxy’ the longest jump; the largest bubble gum bubble; the longest fingernails; the most petted dog; the biggest Barbie doll collection; and much, much, more. It will often inspire kids to measure, calculate, and estimate their own feats while trying to set records of personal best. It’s a great read in the car and a wonderful conversation stimulator, not to mention a really fun and practical example of the ever-present world of numbers.