Consider Fairfax County, Virginia. As Realtors, we can't comment specifically on "good schools," since there's a lot of subjectivity involved. However, you can check the County's schools out on http://www.greatschools.org/search/search.page?c=school&search_type=0&state=VA&q=Fairfax County&st=public or the County's Web site at http://www.fcps.edu/index.shtml
There are a number of areas in Fairfax County with lake-front properties. You might especially consider the Burke area, as well as Reston. There's also Lake Barcroft. Naturally, I'd be glad to send you listings of available properties in those areas.
Hope that helps.