ds1 is in y1, and maths is his strongest subject - he knows his tables, can add 3 digit numbers in his head, etc. Which is great, but at school his teacher openly admits that quite a few of the kids in the class can't yet count to twenty, and every time she introduces a new subject ds1 can do it already so he's not really learning much there.
He actually really enjoys playing around with numbers, and I don't want him put off at this stage, or just left to cruise forever, so he's doing out of school maths at Explore Learning too in an attempt to keep him interested. They've rated him as working at approx yr 3 level (he's doing things like simple probability there at the moment).
So ideally what are good resources for this sort of standard which we could do at home?