My parents were insistent that we eat breakfast every morning. Usually it was some form of cereal, though on cold days we might have something hot. In our teenage years we lived on a farm and breakfast was necessary to make sure we could get the things we needed to do done.
Don't Skip It: Even in sleep we burn calories. It is necessary to have some fuel to start the day and breakfast is it. Our children have growth to consider as well. We don't necessarily need three eggs, bacon, hashbrowns and toast but a healthy breakfast is important.
Check the Cereal: Not all cereals are good for us. Some of the cereals that we think ought to be aren't. Look at the sugar and fat content before buying it. Also note that the "with milk" section assumes you are not using 100% milk. You'll need to calculate that in as well. If it goes over the breakfast budget, you may want to find the kids a new favorite cereal.
This is something you may have to be firm about. My mother did not buy super sweet cereal. The sweetest we had I believe was Raisin Bran. We whined and complained some but she was firm. As a mom and grandmom I understand why.
Waffles Don't Count: Yes, it is easy to stick two waffles in a toaster, add butter and syrup and call it breakfast. It will raise blood sugar quickly and then it will drop it. This can make the first few classes a child is taking difficult. If waffles are part of breakfast make sure there is enough other stuff to keep sugar levels stable.
Recommended: The first thing I recommend is a talk with a nutritionist. Most doctors and pediatricians can refer you to one and some insurance companies will cover it under preventative care. You can explain your child's likes and dislikes as well as cultural food issues and work out healthy menus.
Once you've done that, set up a calorie budget. Caloriesperhour.com can help. The budget is like a bank. What is done physically is a deposit. What is consumed is a withdrawal. At the end of the day you want to have more calories in the account if you wish to lose weight and a fairly even amount if you're just maintaining your current rate. For growing children the nutritionist can give you an appropriate calorie budget.