ROCKVILLE CENTRE - The Department of Education has confirmed that some of the pages were missing from a Common Core exam taken today.

The pages were missing from the third grade math exam in the "form D" booklets. The DOE blamed the missing pages on a printing issue. In total, nine questions were missing from the test.

School districts were informed about the mistake this morning, with some saying they heard about the mistake during or after the exam. Districts were instructed to photocopy the missing questions from another book or ask for them to be faxed from the state.

Rockville Centre Superintendent Dr. Bill Johnson says he's concerned if test results will be valid if some students didn't realize they had a complete book or not.