<p>Well, my son is practicing violin and can’t answer so I’ll give it a shot. Hard for him right now is reading the previous graduate level research documents his physics teacher at the university has given him in order to prepare him to do research this summer. His prof said it will take him at least 10 reads of the 20-40 page documents before he’ll begin to understand it.</p>
<p>Hard is also the kind of math and physics on things like the AIME and Physics Olympiad semi-finals exam. He is understanding more of the olympiad type math but some problems he definitely has no clue about (whether that’s from lack of exposure or something else, I can’t say). Also hard is working quickly to solve problems. He got a 5 on the AIME this year because he ran out of time. He didn’t make the physics olympiad team so I imagine a number of the physics problems were either too hard or too hard to do within time constraints.</p>
<p>I see him working through really long dif equ/real analysis math problems with his tutor and I would guess these problems are hard in terms of trying to problem solve in figuring out a way to approach the problem. They can often work on just one problem in an hour, both tackling it from different angles.</p>
<p>I also remember Calculus III was particularly challenging for him. He did get an A but he spent 20-30 hours a week doing homework. I don’t know what “hard” meant exactly, but I do know he said it was, by far, the hardest or most challenging of his community college classes.</p>
<p>Don’t know if that answered your question or not.</p>
<p>Oh, and for my son, the “hardest” thing will probably be to take 4-5 “hard” classes at the same time that require massive amounts of homework. He is definitely not used to that. While he has always studied 4-5 subjects a semester in high school, with at least two subjects being college level each semester, not all his subjects have required massive homework; in fact, some don’t require much or any at all. <em>That</em> will be the biggest shock I am imagining. My son likes free time to read, think, play, etc.</p>