Like so much of your family vacation, packing is a balancing act — in this case between including everything you need and making sure you can actually lift your bags. No matter where you're headed, this checklist should cover most of the essentials.
Give the kids a role. Every child has favorite outfits as well as clothing that he or she won't wear (and that you shouldn't bother packing). Young children can select the clothes they'd like to bring and set them aside for you. Older kids can do much of their own packing, especially if you help them write up a checklist of their own.
Don't worry about wrinkles. Like aging, this happens even with the best of precautions. Suggest some folding methods, but don't insist on your kids' finessing this. One surprisingly effective technique for kids is simply to roll everything up.
Make each child responsible for his or her own luggage. A backpack and a soft-sided suitcase for each child will do the trick. Let your kids decorate their bags with stencils and stickers — and remember to attach a name tag.
Separate toiletries in sealed, waterproof bags. Lids on toiletries often pop off or open during travel.
Take precautions in case of lost luggage. If you're flying to your vacation destination, pack at least one complete outfit for each family member in each suitcase. That way, if a piece of luggage is lost, everyone still has a change of clothes. Also, pack medications, eyeglasses, and contact lens solution in carry-ons.