A.J.
cubing cheese, veggies, and ham with some goldfish makes a very easy, portable lunch that is well balanced and low on the mess factor.
At that age, my kiddos also liked dipping so I used to slice apples, celery, and colored bell pepper and let them dip in pb or ranch dressing - Note: it was very common for them to prefer the red or yellow peppers with peanut butter and the apples with ranch - kids that age are still experimenting with taste buds.