The way to save money on Texas schools, popular wisdom has said for years, is to not have so many school districts.Consolidate districts, people say, and don’t pay high salaries to so many superintendents.In Tarrant County alone, there are 16 school school districts. Why not combine them into just one? Because it wouldn’t save money, says a report released this week by the Texas Education Agency. In fact, anticipated expenditures per pupil would actually increase by 6.1 percent if Tarrant County school districts were consolidated.Researchers from the Bush School of Governance and Public Service at Texas A&M University, the Texas A&M University Department of Economics and the Center for Persons with Disabilities at Utah State University crunched the data and wrote the study report.The study was mandated in Senate Bill 2, passed by the Legislature in 2013. It examined the potential of school district consolidation in Texas’ five largest counties: Bexar, Dallas, Harris, Tarrant and Travis.Consolidation can often reduce spending, the study says. The cost per pupil of running a small district is usually much higher than in a large district.And Texas has seen a lot of consolidation. In 1935, there were more than 7,000 traditional districts in the state. That number dropped to just over 1,000 by 1995 and has remained stable ever since, with the only increase due to new charter schools.So why wouldn’t it save money to consolidate districts in the state’s largest counties? Costs would go up in every county studied, the report says, with no anticipated increase in student performance.The districts created by that sort of consolidation would be huge, ranging from 803,000 students in Harris County to 341,855 in Tarrant County to 145,846 in Travis County.Managing districts that size just costs more. In fact, savings evaporate once the consolidated school district increases past 3,200 students, the study says.The study assumes no schools would be closed, citing “the political difficulties of closing a viable neighborhood school,” which districts could already do if they saw fit.And districts are already under plenty of pressure to save money.