You can make kale chips and store them airtight for a few days. I actually don't know how long they'll last b/c they get devoured immediately when I make them here.
Slice or cube cheese.
Remove grapes from the stem, wash and keep in a bowl in the frig.
Buy small apples-easier for kids to hold and eat. Or slice them up and add lime juice to keep them from browning. Lime juice may seem weird (I thought so at first) but it's really good on apples. Lemon juice will work too but it's not as tasty imo.
Popcorn will keep fresh in an airtight container for a few days.
Nuts are easy to grab and nutritious. Or make a trail mix w/nuts, dried fruit and even chocolate chips if you like.
Bananas are always easy to grab and eat.
Cook up some edamame and keep in the frig. Or for a different take on a dip, cook up equal parts edamame and frozen peas. Use a hand blender or a food processor and blend with some olive oil, veggie broth and salt to a nice smooth consistency. This is good on pasta too.