Just went last month, and got the three-in-one ticket for Jurong Bird park, the zoo, and the night safari (same place as the zoo).
Those are all great for kids, and they all have shows that give kids a chance to sit and chill out. You can ride an elephant at the zoo. You can feed ostriches bananas, pelicans fish, and flamingoes bread at Jurong. The night safari was a little scary at first for my girls, but they settled down and spent a long time inches from leopards and a few feet from hyenas.
We didn’t take the train/bus/monorail at any of these places; you might do that to save energy as your kids are a bit younger.
The botanical gardens are a lovely place to chill and have a picnic. We joined in on a game of baseball and played with a bunch of dogs (two different activities).
I took the girls to the Raffles Hotel and we had some pastries :lick: and tea downstairs. The durian shaped Esplanade has free fun entertainment most nights at 7:00? The kids loved the crazy show we saw there.
At at Red House (2X) beside the Singapore River, Robertson Quay. Best shrimp (curried shrimp) I’ve had in my life.
Oh, and we did a lot of swimmin’ in the hotel pool.