Frozen yogurt travels well, so does cheese with a freezy pack under it. Ham cubes, cheese cubes, melon cubes, and strawberries make a pretty tray for a birthday party.

Oatmeal is a good choice for breaky (it is low on the glycemic index scale, and a complex carbohydrate), you can also pre cook scrambled eggs in "batch form" and freeze them to thaw and heat later. Meatballs can be done the same way, I simply bake them in the oven like meatloaf, they are great dipped in a little marinara sauce or spaghetti sauce...make them any shape you want...to make it easier to pick up. These travel well frozen well too.

Lastly a snack can be just part of what you normally serve at meal time just add a dip. Dips can be anything, salad dressing, yogurt, peanut butter, even a little hummus is a nice dip.