I concur with the above. You won't find a particularly bounteous (by which I mean, "sized for a growing boy") CS breakfast anywhere -- just a bagel, muffin, cereal, or in some cases (e.g., resort food courts) an expensive breakfast "platter" (costing around $10) with a scoop of powdered eggs, a couple of pieces of sausage or bacon, and/or a couple of Mickey waffles or a slice of French toast. When we stayed at CBR a couple of weeks ago, the food court also had things like design-your-own yogurt parfaits, but again, none of it was served in large portions. If you want a large breakfast at a CS (e.g., a "bounty platter" or omelette ($10) with a beverage (minimum $3) and a fruit cup or yogurt ($4), plan on paying a minimum of $17 per person. (For that price, your money would be better spent at a non-character, an all-you-can-eat breakfast buffet, like the highly-rated Trail's End at Fort Wilderness, which comes in at around $20/adult and $10/child.)
To avoid the time and expense of eating breakfast at a Disney eatery, we always bring all of our breakfast foods from home -- Pop Tarts, mini cereal boxes, fruit strips (or fresh or dried fruit - whole apples and oranges, craisins), and granola bars. Other items that would pack well include flavored oatmeal packets (you can heat water by running it through the coffeemaker without any coffee in it), bagels, English muffins, cheese sticks etc. - and if you're staying in a villa with a kitchen, the sky is the limit -- toaster waffles, frozen breakfast sandwiches, hashbrowns, etc. would all be within reach. The foodstuffs we bring take up about half of a carryon suitcase, but that's okay -- that gives us enough space to bring souvenirs back on the return trip.
Since we're generally in a standard resort room and don't have access to anything beyond a coffeemaker and fridge, I also pack disposable bowls, spoons and napkins, and we buy milk for the cereal from the resort general store and drink coffee from the in-room coffeemaker. Not only do we have plenty to eat for breakfast, but eating in the hotel room is faster and more efficient if we want to arrive at a park for rope drop. Just a thought!