1. Working on Penmanship and Fine Motor Skills – Have them create a comic strip. Works on artistic creativity, humor, fine motor skills and writing skills. New technology does not always give kids the ability to practice their hand/eye coordination and writing skills, and activities like these can make a big difference and help them get engaged in a fun way.
2. Plan a Weekly Outdoor Outing – If you live in an area near the outdoors, have your kids get online or use hiking books to create a weekly place they want to explore. Set aside a half day, and have them work with you to plan the journey – you will be amazed what happens once kids get engaged! Have them pick places (if you have several kids, they can each rotate a week) and get involved with all stages of planning – getting directions, finding ticket prices, planning lunches, etc.
3. Get them into the Kitchen – This summer, have your kids pick their favorite breakfast, lunch and dinner and learn how to make the recipe. Pick something challenging but not overwhelming, and their goal should be to make it on their own (with parent supervision if the stove or oven is involved!) and create a recipe box for themselves with all their favorite creations. If they love spaghetti sauce, have them learn how to make it from scratch. Pancakes and lasagna, same thing. Again, if they write it down, it encourages them to practice their handwriting in a fun way!! 
Image credit: Mads Boedker
Ana is the author of That Crumpled Paper Was Due Last Week: Helping Disorganized and Distracted Boys Succeed in School and Life (Penguin, Jan. 2010). www.thatcrumpledpaper.com
Anna,
It is amazing that we do those 3 things with my 7 year old twin boys. It works perfectly for us. I highly recommend you http://www.Fonts4Teachers.com to practice penmanship. It is awesome for emerging writers. The second step is almost a must, especially with twin boys. And as for the third, I am a big culinary fan, so my children are learning to to small things in the kitchen.
Thanks for an amazin post!