(tl;dr---Make a group of 2, 4, 6, or 8 rising sophomores and you can all pick doubles together. You'll probably end up in Broadway, McBain, Nussbaum, Schapiro, or Wien.)
If you're a Columbia first-year and confused about how this whole Housing thing works, you've come to the right place. This post contains everything you need to know about the Room Selection Process.
The Basics
The Room Selection process has two separate rounds. In-Person Group Selection, known until this year as Suite Selection, is when all suites and doubles are selected. Online Selection (previously known as General Selection), which occurs a week later, is when people can pick into singles. Each group in In-Person Group Selection has a point value and a lottery number. The group’s point value is simply the average of its members’ point values with rising seniors worth 30, rising juniors worth 20, and rising sophomores (you guys!) worth 10. The lottery number is a random number between 1 and 3000 and is completely independent of the point value. Having a bigger group doesn't help or hurt your number since a number is assigned to the group as a whole and not each individual.