C.R.
That's around the age my boys became picky eaters as well. My daughter is 26 months and she still likes everything. The only thing I can say is to look up creative kids recipes online. Or hide the nutritious food in dinners. I used to hide the chicken and tomatoes in cheesy tortilla wraps because my oldest didn't want to eat chicken or veggies all of a sudden. Now that he's almost 6 after I hide something and he eats the whole thing I'll tell him exactly what was in it. Then next time I make it I don't have to hide anything. I used to be able to cover anything I wanted in a little spaghetti sauce. That was the easiest way. Maybe as he sees other little ones eating something at his daycare it will make him want to eat more again. Oh and try letting him dip stuff in any kind of sauce or dressing you can think of. That also worked. Good luck!!