I have been in Cornell for a year, studying Operations Research. For the first half of the semester, every one have to try hard passing three core courses: Linear Programming, Probability and Statistics. The second semester is more relaxing, and it gives you the freedom to learn things you are interested in. I also begin to approach some professors in our department, asking what they do and reading a few papers they suggest.
This summer, I will study and do research (seriously) for a small project in optimization. I always think some advice on research would be helpful in guiding my study.
Here are a few links I searched online:
Secret Blogging Seminar: by recent Berkeley Ph.D. students in mathematics on representation theory, algebraic geometry, knot theory
Funny one: Using analogy of a vacuum cleaner