May I recommend Nearby Nature?
My son and I went to visit and get a feel for their summer day camps. This is the part of the Learnscape, which encompasses fruit trees, herbs, native plants, and vegetables.
Each class has one paid adult instructor, one adult volunteer, and one teen volunteer. There are a max of 12 kids per camp. There is currently plenty of room in the preschool camps while the elementary age camps are filling up fast.
Visit their calendar to read about all of Nearby Nature's offerings!