For true mixed ages, the one that’s stuck for us is simple “categories.”
Everyone spreads out in the shallow end. One person yells a category like ice cream flavors, countries, movie titles, whatever. You toss a soft ball to someone and they have to answer before throwing it to someone else. If you blank or repeat, quick dunk or you’re “out” for that round. No teams, no scoring headaches, and it keeps people moving without turning into a splash war.
What I like about it is adults can play without feeling silly, and younger kids can shout answers even if they’re not strong swimmers. It stays social. People are talking and laughing instead of hyper competitive.
Only thing I’ll add from experience, mixed age games can spike bather load fast because everyone piles into one area. I make sure circulation is solid before we start. Clean filter baseline, skimmer basket empty, and I’ll angle returns slightly to keep that part of the pool from becoming a dead spot. If pH is creeping up near 7.8 the water can feel a little flat, especially when a lot of people are standing in one zone, so I try to keep it dialed in mid 7s.
Low rules, low gear, lots of laughs. Anything that feels more like a conversation with movement instead of “organized sports” tends to work best when you’ve got toddlers to grandparents all in the same water.