Lab Reports: Threat or Menace?

I got the last round of line edits on the book-in-progress Monday night after work, but I haven’t had a chance to do more than leaf through the pages. This is mostly because I had lab reports to grade– the second written report is due Sunday, and I needed to get comments back to the students before they start on the next report.

(Yes, I know, as a practical matter, I could’ve waited until Saturday for that, but I hope for better.)

Grading labs is just about my least favorite part of the job (narrowly edging out committee meetings), and since this is turning into a blog primarily about curricular issues in physics, I thought I’d throw this one out to my readers:

Are you in favor of having students write full formal lab reports? How many should they have to write?

I’m pretty ambivalent about this, mostly because I never had to write formal lab reports as an undergrad.

This may have changed by the time I graduated– they dramatically changed the way the sophomore E&M class worked about two years after I took it– but when I was an undergrad, labs were graded on a binary scale. You came in, did the experiment, printed out the data and answered a few questions, and then handed the resulting packet of stuff to the TA. The TA marked it down as completed or not, and that was it.

This was a whole lot easier on the faculty, but it’s not clear whether it’s better or worse on the student side. Writing formal lab reports does involve some drudgery, to be sure, but it also gives students practice at writing in a technical manner. I’m not completely sold on the idea– the formal lab report structure is almost as artificial as the five-paragraph essay— but it does at least give students some practice in writing about science.

These reports are the bane of my existence as a faculty member, though, because they take so long to grade. It’s not so much the assigning of numerical grades– I can do that very quickly– it’s the writing of constructive comments. There’s really no point in having students write stuff if you’re not going to give them detailed feedback, and line editing their writing takes forever.

Part of the problem is that we’re trying to do several things at once. We want them to understand the physics involved enough to talk about it sensibly, we want them to write in a reasonably competent manner, and we want them to do data analysis and error propagation. Trying to do all of those at once is overwhelming for some students, and trying to grade them on all three at once is overwhelming for a faculty member. If a report contains confused physics, no paragraph breaks, and no error analysis, which of those is the most important to address? There’s a kind of error fatigue that sets in after a while, and it’s really hard not to let stuff slip on page five after marking up every single paragraph of the first four pages.

I don’t know a better way to do things, though. So I have the students doing three lab reports per term, which gives me just about enough time to finish marking up one lab before the next one is due. In the modern physics class, I have them do oral reports for the other four labs, which are not without their problems, but at least they’re over quickly.