I am currently writing emails to potential grad school advisers. I have no past publications, however I am about to write a paper (1st or 2nd author) as well as an honors thesis. Should I list these on my CV?
I personally wouldn't include either the planned thesis or the planned paper under an explicit Publications section. If you do choose to include the thesis, however, be sure to qualify it as "planned" or "pending". Alternatively, you could note elsewhere in your CV, or cover letter, that your program requires an honors thesis, and that you plan to write one on the topic of X.
I agree with Vanadium 50 that you don't want to put anything on your CV that you haven't actually done. What I have seen is that people will sometimes have a seperate section for "works in progress." More typically this is for where one has written and submitted a paper and it's currently in the review process. You won't get much credit for something that doesn't exist yet.
That said, you might want to mention some details about it in a cover letter. For example...
I am a fourth year physics major. For my honours thesis I've been working with Professor A studying (subject) using (special techniques). We have successfully generated (an important result), and my role in this was (what you actually did). Next year I will be looking to apply to your graduate program and...
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