Some TAs are a miss, others are a hit. Unfortunately my orgo TA was VERY unprepared and we ended up leaving in 15 minutes instead of an hour and twenty minutes. Good TAs have some kind of material prepared to go over and can answer questions well...so yea. But on the bright side, there are other TAs that know their stuff and you can go to their sections sometimes and email them and whatnot.

I totally agree with Domo.. some TA's are win are some are fail. My physics II TA last semester had a really bad accent that no one could understand and some people just ended up not attending the TA session at all. But this semester, I have TA's for Differential Equation and Calc III and they both are really awesome. They both speak English pretty well and are always prepared.

A lot of TA's set up extra office hours around the time of an exam, and many also set up review sessions.  I know when I had physics 2 with Greco every tuesday or so before an exam the TA's would hold a 2-hour review session.  I only attended two of them, but they seemed fairly helpful.

My orgo lab ta is amazing! He's super quiet but so nice...I ask him the dumbest questions but he always answers non-judgementally, and he never freaks out when my experiment goes awry (not that it happens often....  :D  )

Another good thing about TAs is that they often hold review sessions before exams.  This is really helpful because they devote a lot of time to both going over problems that they consider to be important and answering questions that students are confused about.

I totally agree with everyone who said their TA's were either a hit or a miss.  I did have the lovely experience of switching sections for Calc, so I've experienced both good and not so good TA's. In certain classes, they will introduce some new material, but usually they only teach a small portion where as the vast majority of the material is given by the professor.

TAs are also good for talking about life. haha that sounded creepy. I mean that now that I;m about to be a senior :'( , I talk to my TAs about life after undergrad with regard to grad school and working. I talking to my epidemiology TA today about her experience getting a masters degree from Hopkins and what she planned to do with it. It gave me some food for thought!

I support the general consensus that TA's can be a "hit or miss". I've had TA's for my Calculus II Section, Physics Lab, General Physics Section, Chemistry Lab, and Intermediate Spanish this semester. Out of the five, I really found three of them (Spanish, Chemistry lab, and Calculus) to be extremely helpful!

My TA for calculus was the best- she was approachable, helpful, extremely accurate, and friendly! On the not so great side, my TA's for Physics and Physics lab were not so helpful. Both TA's were pretty unintelligible, as they had both recently moved to the United States. I have no doubt that they knew their physics, but I really felt that my TA and my class had a hard time communicating.  I ended up getting most of my physics help from tutoring sessions at the learning den. In these sessions, a maximum of six students can discuss problems or concepts with an upperclassman who did well in the course. These tutoring sessions are available for a multitude of classes, and there are usually at least three to four sessions per week that you are able to sign up for.

On a side note, I wouldn't recommend the 8am physics section on Fridays unless you are a morning person! In high school, 8am doesn't seem that bad, but in college, 8am might as well be 6am! (It's very hard to learn about angular momentum and whatnot if you're half asleep!)