I just flew up to Canada and back with my 5 year old last week. I found some new crayons called "Twistables". They are crayons that twist out (like some eyeliners do). She loved those and we colored for hours.

They also make Twistables that are erasable. I just purchased the regular type and they were very neat and tidy, came in their own case and were the length of a pen.

Good luck.