It is the responsibility of the teacher to supervise all of his/her students during the entire instructional period.
No teacher should ever leave a class unsupervised, even for short periods of time.
No teacher should ever send a student out of the classroom without an appropriate pass.
No teacher should ever send a student out of the classroom (for any purpose other than emergencies) during the first and last 15 minutes of each class period.
No teacher should ever send a student into the hallway for a "Time Out" or for any other reason, unless there is a certificated staff member in the hallway supervising that student.
Also, teachers are expected to stand in or near their classroom doorways during passing periods to assist in the supervision of hallways and to welcome students to class.