A lot of the classes you will initially take for McCormick or a STEM Weinberg major will be the same so for your freshman year it doesn’t really matter what school you are technically in. For example all of the freshman Chem classes have a mix of Weinberg and McCormick students and you can use the credit for a degree from either college. Also regardless of what college you are in most of the classes are open to anyone, like you can be a McCormick major taking music classes. I have a friend in McCormick who is currently taking 3 STEM classes and a class in Greek philosophy, and is switching over to Weinberg next quarter.