<p>rocnation-I don’t know if a teacher can edit a letter. However, he can certainly contact admissions if he wants to by e mail. Here’s the main point though: teachers are human beings too. They are busy and underpaid in general. Writing letters for seniors takes a lot of their time, and they are not paid extra for it. While they consider it part of the job, they don’t write letters for everyone- only the students they think they can vouch for.
Many colleges see letters from the same teacher each year, and they learn which ones are reliable. If a teacher is selective and honest in his/her letters, that teacher’s word is respected by the school.
Your teacher put himself out there by writing that letter. He believed in you. It seems your main reason, and only concern in this situation is the letter. Now that he’s written it- you have changed your bevavior, and it’s disrepectful: sleeping in class, joking, not doing homework and doodling. </p>
<p>Now you are concerned about the letter, but you are really losing much more: your relationship with a teacher who supported you and your integrity as a student. He’s also given the university his word about you, and you have risked that as well. If you keep this up, he may feel obligated to contact them- not about you, but to protect his integrity so that when he does recommend a student, that student is credited for it. </p>
<p>Your teacher is also aware that his students are young, and make mistakes like all of us. It’s not too late to apologize and change your behavior. It may not “save” your letter, but it will “save” your integrity.</p>