Make a big batch of your own trail mix or snack mix. You can make it as nutritious as you want, and tailor the ingredients to your taste. Mix up almonds and other nuts; dried cranberries, raisins and other dried fruits; pumpkin seeds and shelled sunflower seeds; bagel chips, Goldfish crackers (for the beach theme), dry cereal -- anything you like.
Keep in mind that everyone's going to be thirsty as well as hungry at the beach, so don't overdo the salt in your snack mix. The dried fruits will add a bit of sweetness.
Once you have your big batch ready, package it in small, single-serving containers. Small plastic bags that can be resealed are ideal. The individual servings are good for two reasons. They help keep you from mindlessly pigging out. And they keep wind or careless people from adding unwelcome sand to the whole batch of snack mix.
Want something even simpler than a mix? Try the next page.