“The most valuable lessons come not from teachers or textbooks, but from life experience.” ― Charles F. Glassman
Listening to an interview with Yo Yo Ma, he confided that when he was growing up he loved music and moved from instrument to instrument. One day his parents told him to choose one and he chose the cello.
Summer presents opportunities for exploration that may lead into a professional or vocational choice later in life, so paying attention is important. For example, if your child is already engrossed in fencing and wants to spend the summer getting better at it, you may want to let her instead of randomly choosing something s/he’s never done before. But, for those of us who struggle with screen time, look around and see what things your child might explore to broaden his interests.
Home Depot has great classes for kids and they actually go home with something they’ve made! Community colleges might be a place to explore: conducting music, caring for animals or tackling the writing of a novel or poetry. The arboretum will no doubt explore wonderful things such as soil composition and planting within your zone—maybe you’ll even snack on what you plant! There are businesses too, that offer classes (not necessarily designed for children) but that can be fun for a child 10 or 11 and up. Many grocery stores offer cooking classes; Michaels offers craft classes- such as cake decorating and soap making; yarn stores often teach beginners knitting or crocheting.
Begin with your neighborhood and see what shops there are. You might find that some businesses would welcome a small contingent of children with their parents and enjoy teaching them how to make good vegetarian recipes or foraging for edible found food within the city limit.
Then there are individuals who offer lessons from home: sewing, cooking, knitting, gardening, car repair—hobbyist turned teacher. It’s probably a little late for most summer camps, but most museums offer some pretty neat things like space exploration, studying the human body, paper making and raising butterflies.
Don’t forget professional organizations like your local architectural association. From planning, to construction, to tours of your city—lots of fun!