I agree with Nashida that teachers also have a heavy workload, however; I grade almost all of the homework I am assigned in class, this also includes test. My only problem with teachers is that on a night when the band has to play at all four school basketball games (this can be a five or six hour event), they have no sympathy if all the homework is not completed. If there was only an hour or two of homework then yes, it needs to be done; but if five hours worth of homework was assigned I am not going to stay up until 3am to finish all of it, especially if I have a zero hour class the next day.
No I would not change my memories, they are what have made me who I am today; without them I would make the same mistakes as I have before and would ultimately only have another memory I would want to change.