<p>4 Letters:
I already started my applications so the emails were sent to my 3 professors and now I know a professor who wants to write my letter. Since he wanted to write my letter, i'm assuming that it's going to be strong. So if the department i am applying to are ok with it then should I send 4? I think my other 3 are going to be good/strong... </p>
<p>I'm getting letters from my research adviser, undergraduate adviser, and a professor who I've taken a grad course in. The 4th person is the adviser of the graduate student who I had been working on a project with. I didn't ask him to write my a letter because I've never had a course with him and I've had little interaction...but when I talked to him about the NSF fellowship he was very supportive and told me that the letters are crucial and wanted to write me one...but now i'm thinking of asking him to write me ones for grad school.</p>
<p>Emailing Professors:
Also, would it be inappropriate to email 1 or 2 professors in a few programs. I'm afraid that it would reflect bad upon me if I got into the school and didn't end up going there...or is this typical?</p>
<p>4 Letters:
At least 3 MUST be academic. Doesn't really matter who they are as long they're in your field. But as for that student/NSF thing, I'd scratch it out. So I'm guessing that "professor" who wants to write for you is your LOR #1, then the next 3 are fine. Only 4 and no more. The adcoms really do stop reading after the 4th. Also, lesson learned (from my experience), just because someone wants to write for you for one thing, it doesn't mean that they're going to be able to write as well for another thing.</p>
<p>It's fine to e-mail professors- they know they can't take everyone and won't meet these "rejects" at least for a while longer. Look for the thread titled "contacting faculty members!" for tips.</p>
<p>Don't assume that a professor is going to write you a strong letter, ever. I've heard that it's good to ask them directly. I've heard stories of people who had professors ask them if they could write them a letter and then wrote them a lukewarm or negative letter.</p>
<p>Anyway, 4 letters of recommendation is not too much, and actually the NSF and other fellowships recommend 4 letters. Anything over 4 is excessive, I think.</p>
<p>And yes, it's fine to e-mail professors. But when you do e-mail them, don't ask them general questions about the program -- they're annoyed by that, as they're busy people, and a lot of the time they don't know the answer (best person to ask that is the departmental or grad secretary). Instead, ask them specific questions about their research or, if it's a natural science program, if they're taking any students next year.</p>