As a mechanical engineer in manufacturing with around 10 years of work experience, I've discovered that I use some techniques on the job that were never taught in school. I'm sure more items could be added to this list, and feel free to "call me out" if you see things differently, but here is my list of the discrepancies between an engineering education and engineering in the "real world."
Part 1: Education
Wait, I learned calculus?
I'm embarrassed to say that after four semesters of calculus/differential equations, I remember very little of it. The derivative of x is 1 if I remember correctly, but anything past that would have to be reviewed. I do, however, feel that I understand the concepts and could, hopefully, go back and relearn them much more quickly than someone who had never cracked a calc book. Additionally, I still remember the trig concepts behind much of this math, as I do have to use them fairly often. Maybe passing the more-advanced math classes cemented the lower "maths" in my brain for a longer period.
One subject I wish I'd paid more attention to is statistics. I only had one class on this and, after passing all my calc requirements, didn't give it the effort I should have.
With the emphasis on statistical manufacturing methods like Six Sigma, these concepts can be quite important, depending on your role. (Oddly enough, reverse the words and it becomes "Sigma Six" -- a line of GI Joe toys. Adding to this subtle paramilitary theme is that you can get your "black belt" in Six Sigma. Probably just a coincidence...)
Sometimes you don't have to understand everything
Sadly, some might say that education is more about training you to fit in, than actually teaching you to think well. I always had the opinion, likely instilled by the many engineers in my family, that it was absolutely necessary to understand what I was being taught. Knowing the fundamentals is critical, and the amazing thing to me about our field is that everything can be derived from very simple concepts.
It is excellent to understand basic concepts, but on a test, it can be much more expedient to simply memorize a more refined equation that you think will be needed. When you're applying for a job, for better or worse, employers generally look at your GPA, rather than give you some sort of aptitude test. That being said, some employers (Google, for instance) do have a test like this, so maybe there is hope for those who prioritize understanding over getting an excellent grade.
Getting a doctorate isn't always an advantage
More education is generally thought of as a good thing by society, however, past a certain point it really depends on your situation. A good friend of mine graduated with his doctorate, and a pretty spectacular resumé, but when it was presented to my supervisor, he seemed skeptical of hiring a "doctor."
In the end, he ended up working at a another job that he very much enjoys, for an excellent starting salary. He also was paid while in school, so that certainly helped. For some, getting a doctorate means a lot, and it could open up some future possibilities that you wouldn't otherwise have. Like a PE, it's a remarkable accomplishment, but it's not for everyone.
Be sure to check back for part 2 to see what else I think I've learned in my several years of working in the real world.
— Jeremy Cook is a manufacturing engineer with 10 years experience and has a BSME from Clemson University. You can find him on Twitter at https://twitter.com/JeremySCook