He sounds normal. Most 1 year olds only eat one big meal a day (sounds like he's doing that daycare). The other meals may only be a few bites. At that age, my kids always ate well for breakfast, so-so at lunch and 1 or 2 bites (literally) at dinnertime with a few (healthy!) snacks between meals.
He's fine if he's healthy and gaining weight. Remember that for a 1 year old, a serving size is a tablespoon. That's like 1 or 2 green beans! If you are still worried, write down everything he eats for 1 week. I'm sure at the end you'll find that his meals balance out, he's hitting all the food groups and he's getting plenty to eat. Kids won't starve as long as they are offered a healthy variety of foods.