To be clear, classes are not the same as credits. You don’t need to take a specified number of classes, you just need to earn the required number of credits.
Students who can earn credits through AP, CLEP, dual-credit, etc. will not have to take as many classes as students who don’t earn those credits. Even 15 hours of earned credits can mean that you only need to take 4 classes most semesters instead of 5.
It’s generally good to have a couple of easy non-technical electives during your first year to help boost your GPA for ETAM. Once you’re past ETAM and into a specific engineering discipline, having fewer classes might make life a bit easier.