High school teachers: How much time per week do you spend outside the classroom making lesson plans and grading homework?

I am not a teacher, nor do I plan to be. But I have been a teachers aid and grew up with my mother as a fifth and fourth grade teacher, so it may not be accurate for a high school teacher.
From what I saw as an aid, most teachers stay past the end of the school day by either an two or three, possibly four, hours depending on the person and time of the year.
Watching my mother some days she wouldn't get home until seven o'clock. She tried to keep work away from home, but sometimes she would be working until eight creating new power points for math or history or whatever. Granted Almost every year she was teaching the school gave her new standards to work around. Most of the time, reusing old lessons created the year before would work.
I asked my mother this question right now, about how much she worked just outside the classroom, she said at least 25 hours. Almost like a part time job.
for highschool, there would obviously be more grading, but there would also be less direction necessary for the students and so easier lessons.
hope this helps.

I am teaching a course using a new textbook and therefore a new program has to be evolved. I spend an hour or more for an eighty minute lesson . I ‘feel' what it's like to be a student as I plan it. I might spend time looking for a video 2 minutes long ( for the attention span of my students) or make a revision sheet, or look for an online exercise to practice the skill. It's like running a birthday party: keep it active, change type of task every few minutes! But I also pull old tricks out of my hat, I remember what worked before.

Meanwhile, the emails keep popping up and someone tells me that we have another meeting or a voluntary breakfast tech workshop. This drains my energy in anticipation or I feel moved to reply to the email because it won't be done until I do it.

It depends on the time of year and how experienced you are as a teacher.
I've been teaching almost 20 years and with a whole load of resources and experience to draw upon. Planning lessons doesn't take that long. I can mostly do that in my free lessons. Marking is still a pain, but I have learned to keep it to a minimum (there only so much that it helps the students anyway). I try and mark their books once a week. It averages out to about an hour, maybe two every day and then another on the weekend. Overall, maybe 5–10 hours per week.

I know that a lot of colleagues, especially from other disciplines and less experience, who probably put in two or three times this.

I have a low prep job, because I mostly deal with student's who have behavioral issues. But that prep time is replaced with other duties some of which I get paid for.

Overall I would say I spend 10–15 hours per week outside of school unpaid and 5–10 hours per week after school paid- tutoring and clubs. But the tutoring and clubs I do are usually with my students and the benefits of those on self esteem and behavior are of very important and the improved behavior allows me to get more work done during the school day.

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