I'm not sure what your kids will eat, but some ideas:
Calcium and protein:
- yogurt (usually vanilla) or cottage cheese,
- sliced cheese, (my kids love gimmicks and so like the cheese wheels in wax or string cheese sliced into circles)
- ginger snaps and monterrey jack cheese or dates and monterrey jack cheese
Protein and Veggies (plus some iron):
- hummus and sliced veggies (bell pepper, carrots, zucchini, cucumber, broccoli),
- peanut butter (or almond butter if you guys are avoiding peanuts) sandwiches cut into shapes,
- pita with hummus or tuna
- bow tie pesto pasta, (add spinach or broccoli for iron!)
- black beans and cheese,
- peanut butter crackers (whole grain or graham)
- hard boiled eggs
Protein and Veggies or Fruit:
- corn or edamame
- grapes or bananas or cherries or blueberries or raspberries or dried mango or watermelon
- popcorn (air popped if you can swing it), with nutritional yeast = high in folic acid and iron