Hi there, I'm a resident of Kingstowne. As of now, the Mount Vernon/Route 1 corridor, as FairfaxCoResident said, is a patchwork of good and not so good areas, though its set to improve over the next decade. Kingstowne is a large planned development with trails and landscaped open space, along with its own towne center, and is convenient to 95, 495, and 395.
As for schools, the Mount Vernon area is considered the least desirable in Fairfax County, with two high schools: Mt Vernon and West Potomac, though West Potomac is considered the better one. As for Kingstowne, the larger Southern 2/3 of Kingstowne (south of Kingstowne Boulevard) is districted to Hayfield Secondary (middle and high, though segregated), and the smaller Northern 1/3 is districted to Edison High. Hayfield's F/R rate is the lowest of all the four mentioned above, but its test scores are about the same as the rest. Edison is comparable to West Potomac. And by the way, Mount Vernon and Edison are IB schools, while West Potomac and Hayfield are AP schools. You can check the high schools out for yourself at
Fairfax County Public Schools - High Schools, and you can do the same for elementary and middle, as these schools are similar since they feed into these high schools. Each school's 'profile' offers more info, with detailed demographics and test scores available.