1. Sneak in soy. Even if your kids don't have milk allergies, soy milk is a terrific source of healthy phytochemicals. My kids don't like soy milk but don't notice when it's hidden in a recipe. I use the low-fat kind in some recipes that call for milk, such as oatmeal, mashed potatoes, and sauces.
2.  Use whole-wheat flour.  If you think your kids will notice, start by using a 50/50 ratio of whole-wheat flour and all-purpose flour in your recipes.  They will be getting more whole grain fiber without the fuss.
3. Use whole ground Flax-seed meal which is full of fiber, lignans and omega-3 fats.  All good for fighting cholesterol.  Add 2 tablespoons to your hot or cold cereal, pancakes, waffles or bake it into your quick breads and muffins.
4. Use fat-free chicken broth or fat-free milk in mashed potatoes, soups, gravies and stews.  Most pediatricians state that kids don't need full fats after age 3.  You can wean from full fat to 2 %, and then to 1% and finally to skim over time.  Some claim you get all the calcium and Vitamin D of milk without the fat with skim milk.  
5. Replace some of the fat in baked goods with applesauce, plain nonfat yogurt or low fat buttermilk.  0% fat greek yogurt from Trader Joe’s can substitute for sour cream in dips, sauces and baked goods easily.
6. Coat chicken and fish in breadcrumbs rather than batter, and bake them instead of frying them.  If making your chicken nuggets use whole wheat flour instead of breadcrumbs or if there’s an allergy gluten-free cornflakes broken up gives taste and texture.
7. 1% buttermilk can be used to substitute for heavy cream.
8. Use canola oil or olive oil when sauteeing because they contain good fats.  Or better yet use a cooking spray - preferably not from an aerosol can.
9. Whole wheat pasta instead of white pasta and try switching to brown rice rather than white rice.  The amount of nutrients in the whole wheat and brown rice vs. their pale friends is amazing.  Might take some getting used to, but worth a try.
10. Use whole foods rather than packaged or processed whenever you can.  The whole grains contain more of their nutrients and don’t contain preservatives, chemicals and sodium.  If you use canned sauces, broths or bean -- look for a low sodium alternative.

Fun Food Pyramid

List of links:
www.mypryamid.gov
www.kidshealth.org