Not sure if this out of your way but the Little Klubhouse on the Fort Worth Christian campus was a wonderful start for my 3yr old. at the end of the term. he could write his on name. Now he attends FWC and its a great.
Also Compass Christian in Colleyville has a good program for a few days a week, and I have visited Pre-School Enrichment Center in Keller before and have heard mainly positive reviews (though not my style).
Re: PreK 3 in Keller/Southlake/Roanoke area