Parents can't remove previous teachers from their accounts.
Your connection to a teacher/class will naturally be removed when a teacher archives their class at the end of the year. This will remove the ability for you to message the teacher and view reports.
However, Story and Portfolio posts are designed to remain in your feed so that the memories can be kept there :). As your child's new teacher starts to post, the old posts will be pushed down so you'll only be seeing new posts at the top of your newsfeed.
That being said, you should no longer have an active connection on your account to a previous teacher. An active connection would mean that you could still message this teacher. If you are still seeing an active connection to a previous teacher on your account, please reach out to them and ask them to archive their former class.
If you are having any issues getting in touch with them, please contact us at firstname.lastname@example.org so we can assist you with this process!