oh, i got it!

here is how we solve all the problems!

1. require every child that is able to bike to school. this will go a long way towards combatting childhood obesity. it will also make motorists more aware of and proactive of bicycle safety. i mean, you wouldn't want to cut it too close if you were passing a bunch of munchkins who were bicycling to school, would you? this mandate, the every-child-bikes-to-school-act, will of course effect some changes in the real estate world.

2. real estate prices, specifically residential prices, for properties nearest to schools are going to increase. this is because children who have to bike farther to school will infer that their parents do not love them as much as the parents of more centrally-located children. this is okay and good. a little competition for the same properties will create a district where everybody wants to be, similar to the traditional "market" of traditional downtowns.

3. prior to this point, local planning departments need to wield the power of zoning. this power is oft abused nowadays to create places that are shitty. but, in this specific instance, the power of zoning can be used for good and not for evil! in areas around schools, overlay zones for denser development will need to be created. these overlay zones will require housing that is reserved for families of all income levels, and it will carry a requirement for public parks and street-level retail. this will ensure that the development focus around schools will be directed in a manner that is healthful to the communities.

4. more progressive communities will, i'm sure, want to implement the incredible ideas of henry george, whose 'single tax' on land allows communities to claim the monetary gains of socially-accrued real estate values. economic rent should, of course, be shared by society; and these new school-driven districts are a great chance to start implementing this idea.

i think that covers the problems inherent in sprawl, childhood obesity, improper motorist treatment of bicyclists, AND real estate inequality.