Why am I so bored, even though I don't sit home all day?

I'm a teenage girl and this summer i've been super bored. I have a fairly busy schedule: most weekday mornings I help with a childrens art program for 3 hours, I student teach dance classes 2 nights a week, a exercise daily, belong to a swim club, I babysit, I run errands and hang out with my family and I hang out with friends typically at least 3 days a week (sometimes even more.) whenever I am home I find myself extremely bored. Does anyone have any idea why I am feeling so bored? Or do you have any creative suggestion on how to entertain myself? I would like to experience a great summer and being bored half the time doesnt help.