my avatar is my oldest granson we were out in the field cutting logs,and he loves it,going on the quad bike.
He looks about the same age as my grandson, going on 5. Make an impression on them now, and they'll carry it with them long after we're gone.
That is the right age to work with them on things like gardening, building birdhouses and feeders and even painting some things. Put that spark of being able to do things that are real and worthwhile.