We live near the St. Louis area and there are great free resources like the St. Louis Zoo and the Science Center.
You can spend a whole day at each covering multiple school lessons. And the kids get to be out of their normal learning environment.

Another is to do age appropriate science lessons. Cornstarch/water for younger kids, done outside and hose them off afterward by playing in the sprinkler.
Kitchen chemistry is great and there is a whole world of it out there that doesn’t involve baking. Simple experiments that can be easily taught with household ingredients.
Household physics is another category with some great resources.

My personal favorites are the ones you can do the same experiment with multiple ages and discuss different aspects. Oil/water is a great example. Magnetism is another.