We live in Mt Vernon and my step daughter goes to Baltimore Montessori Public Charter School. They have prek3 and 4, although the 3 may only be half-day (she was at another place for that). In Baltimore, charter schools are run by the school system, which makes them much more reliable than in other cities. It was a lottery to get into the school, but it wasn't too difficult, and it is really a great school. Other people love Roland Park elementary, and you could probably live somewhere zoned for that school and commute pretty easily.