N.W.
My son goes to St Charles preschool and we LOVE it! He only goes three mornings a week, and it's $160/month. You can find more info here: http://stcharlesbloomington.org/sites/talexander/. They do offer all-day preschool (and have a daycare if you need for your younger son). I don't know much about other preschools, only the ones we researched. Those were all about the same price, and we felt we got more out of St. Charles. As for what school district you're in, you can contact MCCSC at ###-###-####.