Advice (broadly defined)
Advice on asking for recommendation letters: Pamela Harris, Tom Roby, Ravi Vakil
Lots of good advice for math grad students: Ravi Vakil
Advice for succeeding in a college math classroom (some advice is specific to Carleton, but most is more generally applicable or an equivalent resource might exist at your college): Carleton TRIO
Lots of resources for REUs, applying to grad school, connecting with other mathematicians, etc.: OURFA2M2 (I also highly recommend subscribing to their newsletter)
"Our Stories" talk about questioning and finding your place in math: Juliette Bruce
Teaching related things:
Analog Inspiration: Prompts/Tools/Ideas for incorporating AI into teaching and learning in ways that are productive and don't replace thinking: Home Page, Cards/Prompts
Mathematical Axioms
Mathematical Axioms (from Federico Ardila):
Axiom 1. Mathematical potential is equally present in different groups, irrespective of geographic, demographic, and economic boundaries.
Axiom 2. Everyone can have joyful, meaningful, and empowering mathematical experiences.
Axiom 3. Mathematics is a powerful, malleable tool that can be shaped and used differently by various communities to serve their needs.
Axiom 4. Every student deserves to be treated with dignity and respect.
Useful tools/webpages
Combinatorial Object Server: http://combos.org/
Online Encyclopedia of Integer Sequences: https://oeis.org/
arXiv: https://arxiv.org/