Food Issues

I have a 2 1/2 year old that started 2 months ago. I try real hard to feed nutritious home cooked meals for the kids in my care. This new one though won't eat anything healthy. No veggies or anything that may have a veggie in it. I am lucky to get him to eat anything out of the 3 meals (breakfast lunch and snack). I know he is starving when he goes home because when mom gets here the first thing out of his mouth is that he wants chicken and fries. Based on moms response it looks like 4/5 times he gets what he asks for.

So how do I fix this? I don't want him to starve all day not only is it bad for him but I have more behavior issues out of him than the other 6 I have that are in the same age range. I attempted to talk to mom about it and she told him needed to eat what I give him but I think he is content to wait for McDonalds when she picks him up.