J.F.
I went through this with my son when he was between two and three years old. He'd sit there with a bite of food in his mouth and just stare at me. It didn't matter what I did, what I fed him, what tricks I used... He just wouldn't eat. Of course, he was fabulous at daycare, but at home? Forget it.
After a while I just gave up. I figured he'd eat if he was hungry. Plus, at that age, his stomach was so small, that a normal portion to me was just gargantuan to him. I started scaling down his portions and as time passed, he started eating "normally" again. I'm pretty sure it's just the age.
Hang in there. I know how frustrating this is! I felt like I was letting him starve by not making him eat his whole dinner, but kids won't let themselves go hungry. :)