Honestly, this is something that I struggled with a little bit. I found it hard to develop a relationship with professors when my class size was over 100. Go in to office hours regularly with good questions and have a chat with professors you would like to have write you a letter of recommendation. Ask them how you can do better, and show that you care about learning. Basically, you want them to write you a personalized letter, not one that is generic and simply lists your ranking in the class.
Some pre-meds I know simply asked the professor at the beginning of the semester what they needed to do for the professor to write them a good letter. I don’t know if I would go this far. If you develop a good relationship and let the professor remember your face and who you are, they will usually be happy to write a letter for you.
With that in mind, be sure to ask the professor to write you a letter at least a month before you begin filling out your application. The first year I applied, I did not do that and discovered that one of my professors was leaving on a sabbatical to Europe in June. Hence, she had to rush her letter.
On the other hand, letters can’t be written too early. I believe that AMCAS prefers it if the letters are written within a year of your application. Thus, this year I had to ask all of my letter writers to resend their letters. *embarrassing*
Who to Ask to Write You an LOR
1. Professors who know you well. You don’t even have to do that well in their class. I would say if you got a B or better in their class, it’s probably ok. If they know you well, and know that you are smart, talented, and committed to medicine, they will write you a great letter of recommendation.
Also, who writes a letter for you matters on what the school’s requirements are for LORs. Most require 2 science professors and 1 humanities professor. No TAs. Check beforehand to know who you need to write you letters. If you use an electronic system like BYU uses, you can send in a letter packet with all the letters required for the schools you are applying to. If schools receive more letters than the required amount, they will still read them. Also, you can usually double count one letter. For example, I took a class from my PI, so I used his letter as a combined science faculty and research letter.
2. Your research advisor. Make sure you have a great relationship with your PI, because research is a big deal in med school.
3. A supervisor for an extracurricular activity: this can be a volunteer coordinator, a doctor, etc. Some schools like the University of Utah require a letter from a healthcare professional.
Most importantly, make sure your letter writers are people who will write you good letters. You can even ask them if they think they will be able to write you a good letter. If they say no, find someone else.
LORs Count… A LOT!!
I didn’t know how much LORs mattered until I interviewed. One interview I had was done wholly on my letters of recommendation because that’s all the interviewer could access at the time. I got accepted to that school. In other interviews, I was also asked about different things that my letter writers wrote about me that were not on my application. So, who your letter writers are and what they say do matter.