aggressive behavior

Question
I have a purebred lab who has always been possessive about her food. If she has food in her bowl and anyone walk near her she will growl. When she was a pup we took away her food occasionally thinking we would prevent that behavior. She also growls frequently when other kids are in the house when they look at her or pet her. Sometimes she will go up to them like she wants to be pet and when they pet her she growls.

SHe has been fixed.

Answer
The key to most behavior problems is approaching things using the dog's natural instincts. Dogs see all the people and dogs in the household as a pack with each having their own rank in the pack and a top dog. Life is much easier if the 2 legged pack members outrank the 4 legged ones. You can learn to play the role of top dog by reading some books or going to a good obedience class. A good obedience class or book is about you being top dog, not about rewarding standard commands with a treat. Start at http://www.dogsbestfriend.com/ For more on being top dog, see http://www.dogbreedinfo.com./topdogrules.htm  That site has some additional material on children.  

As for the food bowl, start out only putting part of th efood in it.  when she finishes add more, and more again when she finishes that.  Soon she will welcome having your hand near her bowl.