Hahaha, well I used to be the biggest milk-drinker EVER! (Cereal for breakfast and dinner, a carton at school, and usu. a glass afer school), and I LOVE soymilk to death. Vanilla or plain, they're great!! But since your kids prefer the taste of cows milk, I would definitely recommend rice milk. I just bought some recently to see what it tastes like and it tastes a LOT like cow's milk, which was actually a turn-off for me. It does taste good in really sweet cereals though, whereas soymilk sometimes doesn't (well, for me it always tastes great, but some people think it's too sweet).My mom loved it, and she's an omni who tends to not even try my vegan dishes just because their vegan. So, try rice milk first. Don't even tell them , just make their cereal for them and they won't notice.
Almond milk tastes like, well almonds. It's pretty gross, I think. It is seriously like drinking almonds, the only way I could down it was in my Honey Nut Cheerios (I didn't completetly cut out honey).