One thing my younger kids already do frequently is listen to story tapes ( the "Adventures in Odyssey" programs are a particular favorite ) while they color or draw. Since my 8-yr-old will listen to the same stories over and over and over, we encourage him to use headphones.
Right now Jason and one of his buddies are sprawled out on the living room floor with a 3-ring binder, empty trading card pages, and a gazillion baseball cards which they are sorting by team and putting into the pages. So working on a collection or a hobby like building models can fill time currently occupied with television and video games.
Letter writing is somewhat of a lost art these days. Email just isn't the same as a letter written on stationery with your own handwriting and mailed to the recipient. So an evening every once in a while spent writing letters to family members, far-flung friends, missionaries, soldiers would be an excellent way to practice writing skills and bless someone else at the same time.
Create greeting cards with an assortment of papers, inks, and rubber stamps! You can even make your own envelopes from white copy paper, or use scraps of leftover gift wrap for a one-of-a-kind special delivery.
There are tons of ideas online. Check out one of my favorite sites for learning activities for kids - http://www.enchantedlearning.com/ There is enough on that site alone to keep your kids busy for an entire month! Another favorite resource of mine is Family Fun magazine, and its online counterpart - http://www.familyfun.com/
Go to The Tree House for a whole lot of ideas for Old Fashioned Family Fun.
Author Jan Brett's website is full of fun activities, games, coloring pages, and more for children. http://www.janbrett.com/