1. Air-popped popcorn. Even cheaper than the microwave and no unpopped kernels.
2. Jello. Add some fruit and it's an instant snack that won't really ruin their dinner.
3. Homemade snack mixes. Mix up the different leftover snacks (crackers, pretzels, cereal), add a little melted butter and seasonings, then toast in the oven.
4. Make it a "mini." English muffin pizzas, tiny burgers, and tortilla chips topped with retried beans all make mini options that taste just as good as their bigger versions.
5. Chocolate covered bananas. Cut in half, use skewers, freeze, and dip in melted chocolate (or cheat with magic shell).
What are your favorite frugal snacks?