-Try not to stress about the nuances of nutrition: fat, protein, calcium. Instead, aim to have your children eat fresh, natural foods more than anything else.
-Aim for variety: Pizza, pasta and grilled cheese don't count as different.
-Try to have your children eat when they're hungry and never after they're full.
-Unless your child loves surprises, agree on everything that goes in the lunchbox. But don't save vegetables for dinner - tell them there has to be one vegetable and one fruit. It's the right lifetime habit.
-Pack foods you know your children will eat. Don't keep packing yogurt if they don't eat it. Otherwise they will open their lunchbox and seek-and-destroy those items.
-Avoid trying out new foods. Save them for dinner when you can discuss them.
-Never pack the same lunch two days in a row. Variety makes nutritional sense and gets kids used to the idea that they eat different foods on different days.
-Even if your child only likes two lunches, alternate them. Eventually you'll be able to add other foods.
-Make sure lunch is different from other meals. That doesn't mean children can't have breakfast for lunch - just make sure it's not the identical food.
-Don't pack chips or salty crackers, a gateway food to chips, regularly. Your child will encounter them often enough at school and at friends' houses.
-Do allow your child to have pizza or school lunch once a week. It may be nutritionally inferior, but it's cool, and being cool matters.