Some of my favorites from this lise: build a fort, nature walk, scavenger hunt, cook/bake, make and blow bubbles, tye die, homemade salt clay, make a milk carton boat, pet rocks, "travel" around the world (food, games, etc. from all over), make slime... Good Ideas, Kids Stuff, For Kids, Free Summer, Summer Activities, Fun Ideas, Fun Things, Summer Fun, Summer Ideas
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33 Activities Under $10 That Will Keep Your Kids Busy All Summer - there are some *awesome* ideas here!!! :)
For summer: Mom puts together lists under five different categories - Oh the Food we will Eat, Oh the Service that can be Done, Oh the Places we will Go, Oh the Crafts we will Make, and Oh the Activities we will Do; every Sunday, as a family, they plan out the week w/activities from the lists.