There are loads of activity books for boys and girls. Get mazes, sticker books, stacks of colored paper, playdough and just let them at it. Simple board games like Candyland. Have fun with photo apps, use filters, make videos.

It really helped my daughter to show her how to break down and prioritize her tasks. I think she would be overwhelmed by the entirety of her assignments and would just balk at the amount of work. We broke it down for larger projects so she would do just a little bit a day. Also, organize his homework so he tackles the hardest parts first (after he's refreshed with a snack etc) and the assignments get easier as he goes through them. That way, he'll be less likely to lose motivation and focus (at least that works for my daughter)

This is super silly but I turn housework into my workout. If I'm sweeping, for example, I clench my core and really move with intention. If I'm cooking, I do leg lifts in the kitchen. If I'm carrying items from one room to another, I use them like free weights to work out my arms a bit and so on. It's the only way I can fit it in!

I did a minimum of 4 books daily. My daughter loved Goodnight Songs, Where the Wild Things Are, Oh The Places You'll Go, Mr. Brown Can Moo, Little Blue Truck, and Hug. She also loved all those touch and feel books and lift a flaps.