Just be outside. Kids need unstructured playtime. Don’t bring toys or anything just let your kid be in the grass, dirt, playground whatever. Let them get bored and watch how quickly they get creative
There's the five by five program. It gives free admission to the different museums & the zoo for any child 0-5 years old. https://denvergov.org/myfivebyfive/
We just started swim lessons with ours and she loves them! Nice excuse to get out of the house. I have a friend whose baby is in gymnastics (which just sounds so cute). 😂 There are also storytimes and stuff like that at local libraries that you can sign up for!
If you have snap benefits you can get into the zoo and all museums for $1🥰