From the National Center for Education Statistics:
The National Center for Education Statistics released a new First Look report today December 26, entitled Selected Statistics from the Public Elementary and Secondary School Education Universe: School Year 2015-16. This report introduces new data concerning public elementary and secondary education in the United States collected through NCES’ Common Core of Data program.
The report also shows that there were 98,456 operating public elementary and secondary schools and 18,328 operating local education agencies in 2015-16. Those schools were attended by 50.3 million public elementary and secondary school students, which is an increase of less than 0.1 percent from the student membership in School Year 2014–15.
Direct to Full Text Report (26 pages; PDF)