Douglas County, Colo. 420%
Osceola County, Fla. 296%
Loudoun County, Va. 281%
Elk Grove, Calif. 240%
Katy, Texas 223%
Clark County, Nev. 219%
Guilford County, N.C. 200%
Gwinnett County, Ga. 199%
Lewisville, Texas 192%
Corona-Norco, Calif. 184%
Source: National Center for Education Statistics