By design, most colleges set you up to graduate from college in four years. It's like high school in that you have a freshman, sophomore, junior and senior year. Many students use the summer between their junior and senior year to a land a job or summer internship that will advantage them in their full-time job search during their senior year. And most college career services ramp up during that 4th year. Likewise, employers expect to recruit college seniors in that last year of study. So the 4 year timeline is fairly universal and accepted in both the college and corporate world.
For those studying in an accredited engineering program, it can take five years to complete the undergraduate degree (Dartmouth and Yale come to mind). At other schools, engineering students take up to five classes a semester to finish within four years (UPenn, UMich and George Washington are examples). If you intend to major in engineering, be sure to research this beforehand. Even if it's a mandatory part of your undergraduate education, an extra year of college is an extra year of tuition.
Different life events in college can throw you off course: an illness, death of a family member, a parent's divorce, finances, even burnout and academic probation. These events often come up around college. Unlike high school, college is a place where you'll feel no stigma if you need an extra semester or two to get back on track or finish your degree. In fact, prolonging college (and the good times) is something some students go out of their way to do; we all know students like this. Just know that any delay or interruption can be costly. You will need to cover the costs of those college credits and room and board.
Earning a college degree is a straightforward calculation based on meeting the school's requirements in your major. Coming in with AP credits can help you get there, so can going to summer school at either your current college or a more local one at home. Importantly, if you need to leave school, there are many creative ways to fill in the blanks - online programs, community college, study abroad, even an accredited semester at sea.
Many students never anticipate how difficult it can be to get into some of their required classes for either their major or graduation. College seems like this bright shiny star awaiting their shimmery dreams. It can be a brutal awakening to deal with all the red tape and bureaucracy many colleges impose on students just trying to schedule the correct line-up of courses. At some schools the academic wheels run like finely tuned gears. At others, you will find yourself knee deep in sludge.
Sometime in the middle of your freshman year, take stock of how easy or hard it will be to fulfill all of your academic requirements by year four. And then, before it's too late, start to develop a plan of action. Depending on the school, that might involve meeting with an advisor or just staying vigilant.