This is the coolest lunch ever, not to mention the easiest, and will be the envy of your kids' classmates. If peanut butter is off limits at your child's school, use cream cheese as a spread instead.
Spread one inner surface of a split hot dog bun with peanut butter or cream cheese. Spread the other side with jam or honey. Wrap in plastic wrap and place in your child's lunch bag. Also, pack a whole banana (in the peel) and a small container of toppings, such as raisins, coconut, peanuts or whatever else you can think of.
At lunchtime, your child can peel the banana and place it in the bun, sprinkle on the toppings and eat.