Question: I am a high school junior and generally a very nice, enthusiastic, and charming person, but in my freshman year one teacher just drove me nuts. Now, he is insinuating that he will write a "letter of unrecommendation" to all my colleges! What's worse is that this teacher is notorious for spreading untruthful rumors, and I'm afraid that his letters will contain libel and falsehood. Will the colleges contact me,personally, to verify everything in my teacher's disparaging letter?
Teachers don't automatically write recommendations; they need to be asked by you to do so. In fact, the "Common Application," (which you may end up using for many of your target schools) provides a specific electronic "invitation" that goes to only the two teachers you specify. Colleges that don't participate in the Common Application often have their own forms (either electronic or paper) that you will present only to your selected recommenders. Thus, this teacher who is pestering you will not receive a form nor should he have access to your college list.
More important, colleges do not want letters of reference from freshman teachers. Some explicitly state that your recommendations must come from a junior- or senior-year teacher. (A few schools even stipulate the subjects they must have taught you--typically English + math or science.) Even when a college doesn't insist on a junior or senior teacher, it's a well known rule of thumb that this is the wisest choice. So, if Mr. Rumormonger won't teach you again in 11th or 12th grade, you can politely tell him that his recommendation won't fit the colleges' instructions.
I have a hunch that this teacher may be teasing you and, when the time comes, he won't make good on his "threat." Does he have a reputation for sending out unwanted college letters? If so, can you confirm that it's true and not merely urban legend? If, next year, it seems that he is still geared up to write on your behalf, then you should ask your guidance counselor to intercede.
Colleges will not contact you to verify references. However, you can indicate on your application forms whether or not you waive your right to see your recommendations. I strongly urge you to sign this waiver so that colleges will know that your teachers felt free to speak their minds. Presumably, the teachers you actually select will be those who admire you, so you won't have to fear the content of their letters.
Again, I suspect that you are worrying about nothing, but write me again next fall if this guy still seems to be itching to "unrecommend" you.