I've always wished that math could be taught to children in a way that makes clear the practical reasons for learning the math. One of the culprits is algebra. My teachers, and I suspect most teachers focus first on the mechanical rules of algebra. I guess it's hard to put together the situations where you would apply the algebra.
My brother was working on a geography task last night. He had a map from an atlas and a roughly drawn map. His task was to work out the scale on the roughly drawn map. Together, we went through the steps to calculate the size ratio between the two maps. Then we used the ratio and the scale from the map from the atlas to work out the scale on the roughly drawn map.
That's when he got the "aha" moment of seeing a little algebra in action.