Reddit mentions of Observing the User Experience: A Practitioner's Guide to User Research

UX researcher in the making here. I am currently reading:

https://www.amazon.com/Observing-User-Experience-Practitioners-Research/dp/0123848695

So far, it’s been a great resource in learning the basics :-)

This probably isn't the most helpful answer, but any resources I might have used to learn the fundamentals myself are probably pretty outdated now. Honestly I'd just try to find highly rated books on Amazon that are reasonably priced. I haven't read this one for psych research methods, but looking through the table of contents, it covers a lot of what I'd expect (ethics, validity and reliability, study design and common methods) and according to the reviews it's clear, concise, and has good stats info in the appendix. I had a similar "handbook" style textbook in undergrad that I liked. For practicing stats, I'm personally more of a learn-by-doing kind of person, and there are some free courses out there like this one from Khan Academy that covers the basics fairly well.

But if you can, take courses in college as electives! Chances are you'll have a few to fill (or maybe audit some if you can't get credit), so go outside of HCDE's offerings to get some complementary skills in research or design. I usually find classrooms to be more engaging than trying to get through a textbook at home on my own, and especially for psych research methods, you'll probably have a project that gives you hands-on experience doing research with human subjects (most likely your peers). There are lots of free online courses out there as well if you aren't able to take them for credit.

You guys are making me miss school.

Getting specifically into UX self-study, in addition to a UX-specific research methods book (this is a newer version of one I read in school) I'd also go through the UX classics like Don Norman's The Design of Everyday Things and Emotional Design, Krug's Don't Make Me Think, and Casey's Set Phasers on Stun (this last one being more of a fun read than a practical one).

If she's interacting with a lot of users I would suggest reading Practical Empathy. Observing the User Experience is another great resource for learning about user research. User experience is all about people so it's always a good idea to read up on human behavior, psychology, cognition, perception, learning and memory etc. e.g. books like Hooked, Bottlenecks, Design for the mind, Designing with the mind in mind, 100 things every designer needs to know about people, 100 more things every designer needs to know about people, Thinking fast and slow, Predictably Irrational and I would also recommend Articulating design decisions and Friction.