Original sentence: The new building work included two observation classrooms (one a laboratory and the other a normal classroom), with one way mirrors allowing people in a small room in between the two observation classrooms to sit and observe lessons without being seen
Edited sentence: The new building work included two observation classrooms (one a laboratory and the other a normal classroom), with one way mirrors allowing people in a small room in between the two observation classrooms to sit and observe lessons without being seen, invading the students privacy in the process