Show an interest in what they are interested in. Expand that interest. Honestly Youtube is one of the best resources to show children things. Watch stuff yourself to see what level it is aimed at. In my children's primary school if they had 5 minutes spare or a wet play time so indoors they would play youtube videos like slow mo guys (year 4) and it is science you can see without needing equipment etc.
My children are much older but basically reading to them, getting them to read to you. Maths at the appropriate level but also every day maths, guess how many litres the petrol tank might fill to, if you do this often enough they get really good at guessing, weighing stuff for fun and guessing which might be heavier, ingredients for recipes, are Warburtons crumpets cheaper than the own brand? Get them to look at the numbers. I know you have said possible SEN but times tables. It isn't working it out it is learning the answer. Children can sing songs so they know what order the words come in, it is the same for times tables, it is just knowing the words five times two is ten. Use times table grid so they can see that with every times table they learn they are also learning the inverse so 2 x 5 i= 10, they have learned a fact from the 5s times tables by doing the 2s.
You want them to be as good as they can be in primary to build on that for secondary. But also remember that learning is not always linear. Ds1 was fairly average achieving, secondary saw him excel, great teachers, a confidence boost and he was flying.
Point out things you don't like and things you are not good at. Show them that even as adults we aren't good at everything and we don't love laundry or mopping floors. It demonstrates that we do things we don't like because they are necessary.
Spend time with them, talk about your childhood, things you did, fill their heads with ideas. Learning takes place every day with the simplest things. It isn't all about the classroom.