In the Dallas, TX area.
Public schools:
Garland School District and Carrollton School District are ranked in the top 3 G/T schools in Texas. Both have very objective entrance requirements to the programs. They both have very reasonable cost of living - either renting or home ownership. Carrollton is more central to the area.
http://www.cfbgifted.org/index.htmhttp://www.garlandisd.net/departments/Magnet_Programs/Both Dallas ISD and Denton have Magnet Schools as well.
Private in Dallas:
St Marks, Hockaday, and Greenhill are the top private schools. St Marks is for boys only - and Hockaday for girls only. Greenhill is coed. All three schools provide partial to full rides to part of their student body.
St Mark's has over 25% of its senior class named as National Merit Scholars every year. Typically, these kids are in the top 2/10 of 1% of their age group. Those are some very smart kids.