No, not yet. In January.
No, not now... Look, this is how you show you're three.
Since then he's been practising lots, and then on Saturday he wanted to know how to do all the numbers up to ten. So I showed him that, and how to count on your fingers, though we got a bit stuck at ten. Because don't you know that to do ten is one and zero, mama? The rest, however, he had a good go at.