Can't say for the 1 one old. S/he would probably be happy with an empty storage box for hours on end, LOL.
The 3 to 9 y/o (some games more for one age than the other):
Twister
Uno
Go Fish and Old Maid w/ a deck of cards
Water guns or spray bottles from the dollar store
Bubbles for all. I make my own w/ dishwashing liquid.
Sidewalk chalk (sorry Murphsmom; don't worry it'll rain eventually)which is great for giant self expression and hopscotch.
Finger paints for all age groups. Michael's sells a really extensive artist's kit for about 5 bucks. Has water paints,a pair of safety scissors, brushes, glue stick, coloured pencils and crayons amongst other stuff. Get a big pad of newsprint paper for another 3 odd dollars and you're in business. Splurge on construction paper if you're in the mood.
Plastic binoculars. Not the teeny ones that have plastic lens. Large adjustable lens version sold at various museum shops for 30-35 bucks. One of the best purchases I ever made.
Camping at a state park? They often have nature programs geared toward children.
Up until recently the only battery operated toy I brought was Simon since I felt the eye-hand coordination development was useful and who doesn't like blinking lights and silly noises around the campfire?
I added Kindle to the list this year because I didn't feel like keeping up with 18 books for one kiddo and 16 for the other over a 2-1/2 week trip.
