Shrimp and Grits

There’s some argument on the merits of partial credit - giving students some points for getting at least part of a complex answer correct.  Sometimes, partial credit is beneficial - but the existence of partial credit causes another problem:

Some students simply won’t commit to an answer, hoping to somehow pass on a wave of partial credit.  As an example, consider the question below.  It’s part of a lab write-up where the students measured the pH of a solution of sodium hydroxide using pH paper and other indicators.

Question: Was the solution acidic or basic? _________________
Student answer:  Acidic, with the presence of base

Of course, the correct answer is “basic” - which was very obvious if the student had even glanced at the directions for using the indicators.  But instead of doing that, this student just thought he’d wing it, get done with the lab write-up a whole minute faster, and try to get points for his answer anyway.

I imagine that students keep trying this strategy because it has worked somewhere before.  But not today.

This blog has been very quiet lately.  Sorry about that, but when you’re preparing for five labs a week in addition to lecture courses, things get a little … hectic.

That said, we’re four weeks into the semester down here, and we’ve started our labs.  I normally push the start of labs back a week, so as to avoid having people add my class after we’ve already done a lab and discussed lab safety.

The Labor Day holiday pushed the start of the “real” experiments back even farther - ample time for everyone to pick up one of these.

… so why is it that half of the class comes to lab without even having attempted to buy a laboratory notebook?  It’s not like I’ve forced students to buy something exotic like the $25 lab books I had to buy when I was an engineering undergrad.  Just about every store in the area that sells school supplies stocks these composition books!

Or were these folks simply not paying attention?

You know, if we could figure out how to solve America’s attention-deficit-disorder problem, that would go a long way to solving our other problems.  Just sayin’.