The teacher, 36-year-old Joshua Thomas, was arrested while on the job at Franklin Elementary school Thursday -- in front of students and parents.
Eyewitness News is told Mr. Thomas is now banned from the Hempstead School District property.
He is under arrest, according to police, for exposing himself in broad daylight outside of Hempstead High School.
A detective reportedly spotted Thomas outside the school inside a black Jeep Cherokee -- with his pants down in full view of children.
He was arrested nearby at Franklin Elementary school where he had been teaching for 6 years.
The district released a statement saying:
"This is a serious situation and we realize parents and students might have concerns or questions. The district will have counselors, social workers and other district professionals available for students and parents."
Pollice also tell Eyewitness News, that several witnesses came forth to say Mr. Thomas had done something similar during the week of March 20.
Thomas was expected to be arraigned on Friday.
WEB PRODUCED BY: Lakisha Bostick
NEW YORK AND TRI-STATE AREA NEWS