Full Time Preschool

Creme de la Creme (technically Warrenville). Also, the Compass School has a few area locations. We chose Creme over Compass bc I preffered the philosophy and rotational structure of Creme.

I would personally like to recommend GingerCare. As a mom, and a picky one at that, and a daycare provider for the last 15 years, I think they are fantasitc. They take care of your child personally and the staff is wonderful!

I realize this is old but my answer is for future moms looking for daycare.
And this is in response to the other answers already posted.
Kids Kampus is a great daycare/preschool! They treat you like family, tuition is affordable considering it's in a well-to-do Chicago suburb, and they truly care.
Creme de la Cremes in the Chicago area (especially Warrenville, Westmont, and Romeoville) are not good. They have an extremely high staff turnover, and they only care about you as a customer and see you as dollar signs, not as a family needing child care.
I would consider Kids Kampus, Compass School (both locations), Primrose School, and Goddard School in North Aurora (this is different than the Goddard in Aurora).

I think you need to find a daycare. Preschools aren't full-time. 3 year olds go 2 days, 4 year olds go 3 days, and pre-k is 4 days.

Kids kampus in Naperville at Washington & diehl. It is a daycare, but they offer preschool, as do most, but I think this place is great.

My daughter is going to Goddard. It is preschool and daycare. There are several of these types of daycare/preschool combos in the area. It does not matter the age, the "school" portion is in the am and naps/centers in the pm.