Last night we took the kids to the park down the street and took over the tennis courts. We don't really get to make it to play racquetball like we want to. So we had both tennis courts to ourselves and gave the kids each a tennis ball and a kick ball.
I think "N" had more fun because he was our ball getter person. It's good quality active time to spend with the kids I think. We were able to play, the kids we playing with each other and then we were all able to do it all together.
I suggest that when the weather permits, you need something to do outside, go find a tennis court, and then let your kids take one court and you take the other (if no one else is around) and just let them play whatever and you and your spouse/friend can play. It was a little windy last night but it was really fun and the kids slept really good last night and since "O" was playing with leaves and stuff they had nice relaxing baths.
Try it with the kids and see how they do. I think they will have fun just doing their own thing and you doing yours. When it's time then you can all do it together. For them it's the time spent together that means the most, even if it is just getting the balls.