Camden Children's Garden: We had a great time here with our cousins! This place has limited hours, but kids two and under are free and the rest are $6 if you can go a time that they are opening. Theo loved the carousel, as well as the ability to run around outside and see exhibits.
Milburn Orchards: In addition to picking fruit, they have a petting zoo year round and a newly remodeled farmer's market. They also have a playground, wooden train, sandbox, and other outside attractions for the little ones to play on.
Delaware Children's Museum: This is a fairly new museum, where we can spend an hour or two with our active toddler. There are quite a few different exhibits, but T. spent a large amount of time at this one last time: