I am a new sub. I have worked a total of 3 days so far, haha. I am a bit nervous that a student will leave one of my classes. Last week, in a grade 8 classroom, a student asked to get a drink of water and then didn't return for 10-15 minutes. I was starting to get worried, but luckily he returned eventually. At what point would you call the office to ask them to page the student? I am subbing in a high school soon, and I know from student teaching that students will occasionally skip by asking to use the washroom and then not coming back. If this happened, how would you handle it?