What are strategies you have/use to deal with/help students who all of a sudden (or slowly, gradually, all afternoon) find themselves with 30 minutes left in a lab period, with 2 hours of work left to do. How do you head this off, especially in a large lab section? How do you deal with it once its too late?
To put this in context, this is a junior level advanced laboratory, and the students are synthesizing new materials, and purifying and characterizing last week's materials all at once, so it is a challenge for many students. I am normally quite active, trying to head off problems but some days, if one student is having big problems, I miss other students until it is too late, and they aren't at a convenient stopping point. Then its damage control to get them to a stopping point for next week.
Of course, this could be solved if the students came to lab prepared, so how do you encourage this? Carrots and sticks suggestions would be appreciated!
Adam
I don't have the magic bullet here. When I do a lab on cobalt Werner complexes, there is one synthesis that takes much longer and is much fussier than the others. I clearly warn the students that it is a trickier synthesis and will take longer, so it is not a good choice for everyone (they can choose which of 4 complexes to make). If I have some concerns about a particular student, then I try to gently steer them towards another choice.
Even under the best of circumstances, things go awry of course. Over the years, I have become more firm about just bringing the labwork to a halt and continuing on the next week. Usually, the reaction can be saved and if not, then I am willing to think creatively around the obstacle. I find I am much happier than spending long hours in the lab. Remember that failures can spark learning, too!