Later on, when we were relating this incident to his father, my boy suddenly asked his dad, "Daddy, how to count five plus six?" (because he only had 10 fingers and that was all I taught him). Daddy laughed and went out and bought him a 100 Bead Abacus the next day. (Another excuse for Daddy and Mummy to buy a "toy".)
I've never learned counting using an Abacus before. Certainly not those Chinese or Japanese Abacus and not even a simple basic 100 Bead Abacus. So as usual, I searched around the web and was delighted to find this site RightStart Mathematics. As usual, I'd like to share it with you. Its mission is to help children understand, apply and enjoy mathematics.
Using the Abacus helps the children in math by visualisation instead of mere rote learning. It has a simple explanation of how to use the Abacus to teach math. It even has an interactive Abacus to try out. Here is another interactive Abacus from another site to test out. If you're not sure whether your child will like the Abacus, you can let them try out the interactive one first.
I also like the children's counting songs to help children memorize counting from 6 to 10, about the months of the year and about number writing. Great site for teaching kids math. My kids love the abacus. It has rekindled their interest in math.