AUSTIN — The House voted this afternoon to have a special commission study whether the Dallas Independent School District is too big.

Rep. Yvonne Davis, D-Dallas, added the required study to a bill overhauling school testing and accountability. Her amendment drew no opposition and was approved on a voice vote.

It would create a 21-member “DISD Education Improvement Commission,” headed by State Board of Education member Mavis Knight of Dallas and including educators and representatives of local governments, business and parent-teacher associations.

The study, to be finished by September 2010, would advise lawmakers and Gov. Rick Perry on whether there would be administrative savings, better access by parents to administrators and educational gains if Dallas had small or medium size school districts rather than one large one.

It’s no secret where Davis stands on that question. She introduced a separate bill to divide DISD into two or more districts. It hasn’t moved out of committee.

Davis said she hopes her proposed study bolsters arguments that “the state’s best investment is a smaller district.”

Davis said she intends soon to discuss her study proposal with Sen. Florence Shapiro, R-Plano. Shapiro will be the Senate’s lead negotiator in an expected House-Senate conference committee on the accountability bill.

Davis said, “We don’t lose by trying to evaluate what’s the best size of the school district. We lose by doing nothing.”