He seems to really enjoy it and I'd like to encourage him but I'm not sure how. We do Reading Eggs but I wondered if there was something similarly fun/engaging for Maths?
Most of his day seems to be spent playing (good) but he's been going out to a different class in a separate group for numeracy - it's a huge school. It seems to have sparked an enthusiasm for him. 
Having found Maths erm, challenging, this is a bit of a departure for me and I'd love some ideas!