How I taught my kids

I always think that the most difficult things in the world can somehow be explained in the most simple terms. This afternoon I taught my kids (aged 10 and 7) a few things, such as: how a sailing boat can advance against the wind by zig-zag manoeuvres - I used the mirror as an example to show the reflective angle, and the rocket propulsion to show the reactive force. In addition, I explained the concept of the stock market by starting off with a supermarket growing in size ...