I know it is far away, but do schools usually post up teacher openings starting in March or April for the upcoming school year? If a teacher was to get hired months before the coming school year, does HR wait to process you and want you sign your contract later when it gets closer to the start date or you sign it early still? (Hope I worded that right) I really want to avoid doing a demo lesson for an actual High school class, so when they do interviews in the end of the school year while school is still going on, do they usually ask candidates to do the class demo? If I want to try and avoid the demo for an actual class, should I wait to apply after school is over in the summer? (I know this is kind of silly...)
I would say they start posting in March-April when they know their final numbers for the following year. If there's a retirement, they may post sooner. I would expect a demo lesson if you interview during the school year, but I have interviewed many times and I've only had to do a demo twice. The second time was during finals week and I had to do the lesson for the interview panel (yikes!). It's hard to say if you'd get out of a demo lesson. I think it's a great way to showcase your abilities and I find them much easier than an interview itself, but I can prepare ahead of time, whereas I do not usually know what kinds of questions they may ask. A demo may sway the panel if your interview is not as strong as you hoped. Honestly I'd rather do a demo lesson in front of real students than some of the alternatives out there. I have a friend who had to do a back to school presentation over the summer for an interview. No thanks.
It can vary regionally, or even by district. Around here, February is the earliest you will see postings. Most come in the summer. When I first graduated college, if you didn't have a job by May, you weren't going to have one. Tighter budgets have pushed the timeline back.
It's hard to say you'll avoid a demo unless you get hired the week before school starts. I wouldn't not apply to a job because there might be a demo that's just silly. Between regular school, and summer school or and interview panel, if they want you to demo they will make you demo. Job postings here go up in April if they know there is a need, but many more positions open up in the summer. Depending on the budget and timing of HR most positions aren't processed until the position is actually open which can be and mostly is during the summer.
I've observed several middle school math demos and the students have been very well-behaved. There are usually an unusual number of adults in the room, so they don't get out of line.
I just wanted to relate my experience of bombing in a demo interview for a high school teacher. It was for summer school, and I was to teach a portion of a book "Of Mice and Men". I spent way too much time reading the book and preparing notes on the book itself and didn't allow enough time to prepare a good interactive class. Also, it was for a summer school class of 10 students who didn't participate at all! I knew it bombed as soon as I did it, but the post-mordem was actually helpful and sympathetic. I should have just picked one easy objective (ie. characterization) and done something like Think-pair-share. For a demo class, you should prepare a generic lesson format which you adapt to any reading material....Lesson learned!
Demo lessons are not common where I'm from. When I was job hunting I was never asked to do one on any of the 7-8 interviews I went on(all in different districts) before I got my job. It does sound awkward, especially the ones you have to do in front of adults. I have a video of myself doing something similar in college with my classmates and I cringe everytime I watch it. I tried to teach a whole standard in world history in one 30min lesson. I was stuttering, sweating, and jittery. Funny thing is that even in student teaching I was completely comfortable in the classroom even when I was being evaluated. Not sure if it would still bother me now after teaching for a few years.