Yes, it is generally considered inappropriate and unprofessional for a teacher to take their shirt off in a classroom setting, regardless of the reason. Teachers are expected to maintain a certain level of decorum and professionalism when interacting with students. Removing clothing in front of students can create an uncomfortable and awkward environment and may even be considered a violation of school policies or codes of conduct.
If you feel uncomfortable or disturbed by your teacher's behavior, it's essential to discuss the issue with a trusted adult, such as another teacher, school counselor, or principal. They can address the situation appropriately and ensure that such incidents do not happen again.
Remember, teachers are authority figures and are expected to set a positive example for their students. If you ever encounter behavior that seems inappropriate or raises concerns, it's essential to report it to the appropriate school authorities so that appropriate actions can be taken to maintain a safe and respectful learning environment.