All kids get restless waiting in lines. I'm pretty sure one thing most kids lack is patience. Here are some tips to keep your kids busy while waiting in line.
If you have a smartphone download games... Angry Birds, Where's My Water...etc. The kids will enjoy playing and it will certainly keep them busy.
Hand-held games, like maybe an Etch-A-Sketch and small things like that, that will fit in your bag.
Paper and pencils, this is my last resort but in the end young kids like mine are fairly content just playing tic-tac-toe. It will keep them busy for a little, but not near as long as the other ones.
Snacks! If you are anticipating a long wait for a ride like Peter Pan. Then pick up your snacks and eat them while you wait. Just be sure it's more of an outdoor ride because I'm pretty sure they won't allow you to bring food into waits like Philharmagic.
In the end, if you go to Disney World in the slower time of the year. You shouldn't have this problem to deal with as much especially if you use your fast passes wisely.
Happy New Year!
PS: if you want to know the slow times of the Disney year- check back in a few days to see my post about when to visit for the most pleasurable experience!