I eat and feed my kids your basic Isocaloric -33% fats, protein, carbs. All carbs are complex carbs, most fats good fats (some animals fats for test. and estrogen production and cuz I love butter.)
Oatmeal for breakfast, I stir in flax seed meal, but the kids gag when they see me. I make their's with low-fat milk. Or low fat yogurt and fruit for them.
Lots of leafy and green veggies--they like 'em raw, fine with me. Brown rice, not white, sweet potatoes, not white. Pasta once a week, maybe. Pizza maybe once a month. Fast food maybe once a month. I just don't have chips, snacks, etc. around.
They eat lots of fruit, I don't. I try to limit juices--it's just sugar water. I'll buy diet soda once in a blue moon.
If we have dessert, it's home-made on on my cheat days. Otherwise, no-sugar, low-fat popsicles or fudge-sicles. I hate fake sugar, but a little once in a while isn't a big deal.
I read labels like crazy and cuz, I'm low-thyroid, and cuz my son is an adolescent, no soy products. Soy is very hard on the thyroid and I've read enough to be wary of it's estrogenic effects.
If he's active, he might just be waiting for a growth spurt. It's unlikely that a 10 year old has gotten very carb-sensitive.