Camp Mom SOS (Save our Summer)

I have been batting this idea around for a while and wanted to get a few ideas down before they drowned in the chaos.
I was thinking about fun ways to spend the summer with my kids. They are so curious and active that hanging out at home all day will not be an option past the first week. And it gets so hot here that even running out in the backyard becomes impossible after 10AM. And of course we have to work around nap times and fire time- the period between 2 and 5PM when it is too hot to drive, go outside, cook, or wear shoes.
I want our summer to be a vacation from the structure and busy-ness of the school year. I want my kids to play with each other and with friends they haven't seen since last summer. I want them to have time to do craft projects, read library books, ride bikes, play in the sprinkler, eat popsicles, and look at bugs. I want them to learn to swim, eat picnic dinners by the pool, sleep outside, and catch fireflies.
I don't want them to learn to play video games, watch countless hours of tv, or have their brains turn to mush and undo all the learning they have done so far this year. I don't want to hear "I'm bored" or have tedium turn to squabbles and mischief. I don't want sunburned shoulders or dehydration or over heated kids from trying to go outside and play. I don't want to be a social secretary arranging endless play dates or educational field trips. I don't want to spend tons of money to entertain everyone.
I don't want to wake up on August 1st and wonder where the summer went and have nothing to show for it. Mostly, I don't want to be one of those moms who counts down the days until school starts and is going nuts by June and can't stand one more minute of together time, only to regret it after the first week of school when I realize by children are away from me for 8 hrs a day and all those opportunities are lost. I really want to enjoy my children, have fun together, and have some new experiences.
So- what to do?
Some free local stuff- library story time and splash park. Free kids movies (when they are not trash movies). Reed Creek park nature walks. Clarks Hill Lake picnic and swimming. YMCA pool and swimming lessons and play room.
Some "go once or twice because you have to pay" places- Jump places, summer movies, drive in theater, fort discovery, Columbia zoo, children's museum in Columbia, stables on base, strawberry farm.
Day or overnight trips- Atlanta aquarium, Olympic park, m&m world, kids museum, stone mountain, 6 flags, myrtle beach, Savannah/tybee island, Hilton head, Charleston, ??
Big trips- week in Tenn to Great Smoky Mountains for family reunion. Long weekend at the beach. Road trip to MD/DC?
Things to do/experiences: make freezer strawberry jam, make a peach pie, have a camp out, learn to swim, read a whole new series of books out loud, read the Book of Mormon as a family, have a cousin pen pal club?, learn something new, play in the rain, keep a summer journal/scrapbook, grow a window garden (ants, slugs, squirrels, etc will eat it outside).
Day camp: usually I let Lenna and Andy now that he is old enough, choose a week-long day camp to attend. They have so many choices here- everything from the traditional day in the woods with canoes and swimming, dance, art, drama, sports, science, math, sewing, cooking, etc. A part of me feels like they deserve the opportunity to learn something new, and honestly, a whole week with one child at a time would be great! But the cost is unreasonable for two kids who don't need the day care.
I thought about a camp mom- a weekly theme to plan activities around for our family. Crafts, snacks, books, movies, trips, etc all based around a theme like outer space or sports or Australia. Or maybe mini home day camps to learn a new skill like cooking or sewing or nature camp. then I thought about inviting some friends to participate as well. Then thought about using a mom swap approach- get together a group of about 10 kids and rotate houses each day a for a week, maybe two or three times during the summer. One day of chaos that I am in charge of entertaining the group with something fun like water games, crafts, cooking, stories, etc, in exchange for four days of silence and mom time, or at least kid-free grocery shopping, while the other moms take their turn. Seems do-able right? Maybe?
What do you think? What is your survival plan for the summer? What are your favorite summer time activities? Want to join a kid swap?