## Physics Blogs

I am delighted to have started reading a lot of physics blogs recently. In fact, they are beginning to make up the bulk of my PLN, productivity-wise.

One quick note: Mark Hammond recently wrote about intentionally showing (and having students create) mistakes. Some ideas are his, and others he attributes to other people (particularly Jim Doherty), but I am going to give him sole credit for the purposes of this post. He talked about showing two problems side-by-side—one with an error, and one without. The students must figure out which one is correct and where the error is.

This reminds me of the exercise I got from Assessment FOR Learning, described here. I recently repeated this exercise (with the question: “Why is the area of a right triangle $\frac{1}{2}bh$?”). Again, I had one example that actually answered this question (by combining two right triangles into a rectangle), and two examples that just explained what to do with the formula. The response from the students was intriguing: the first class was evenly split among the three as to which actually answered the question, whereas the second class picked the correct one (by a vote of 18 to 2 to 2).

Still, this is a difficult question for the students. I am having the students write short papers explaining why different algorithms give the correct answer (these algorithms are: standard multiplication algorithm, long division, “multiplying across” for fraction multiplication, “common denominators” for fraction addition and subtraction, “invert and multiply” for measurement fraction division, and “invert and multiply” for partitive fraction division). The students can submit drafts, and I will comment but not grade them. The final draft will be due at the end of the semester.

So far, students are still mostly struggling with answering the question that was given, although some progress is being made.

Okay, if it seems like the whole “physics blog” topic was just a cover for me to talk more about Assessment FOR Learning, that’s because it was. Sorry about that, physicists of the world.

### 5 Responses to “Physics Blogs”

1. Andy Rundquist Says:

Ya got me!

How is the “I’ll make comments but not grade it” coming along? I’ve been doing a lot more of that with big writing projects, encouraging the students by saying it’ll help them in the long run. -Andy

• bretbenesh Says:

It is going reasonably well. I have had about 2-5 students take advantage of it each class period, which is probably about what I expected (I have 37 students). I have had probably 10 students get feedback in all.

You shared this concern earlier: the problem with giving students more responsibility is that they have to be responsible (I believe your direct quote was “giving them enough rope to hang themselves”). I am doing my best to help them by reminding them, but they ultimately have to do it.

I am happy so far, considering that I made this change mid-semester. Next semester will be the real test, when I start the semester with this policy. Bret

• Joss Ives Says:

How do you ultimately give them marks after the feedback cycle? For some types of assessments it seems that you could develop some very nice rubrics that you would be using on some sort of final assessment and both you and the students could use these rubrics in the feedback phase.

• bretbenesh Says:

Hi Joss,

It is somewhat complicated, but here it goes:

The class and I made a list of criteria of a “good explanation.” See here for more details. This will function as the rubric. This is a SBG-ish class, and there are eight topics they need to know. Their job is to accumulate evidence that they understand each topic, usually (but not always) in the form of a quiz question. I am counting the papers to be 2-5 pieces of evidence. At the end of the semester, I will use my best judgment as to how convincing the students were (according to our rubric) in doing what the paper was supposed to do; I will give them a proportional amount of evidence.

Which reminds me: I need to do a couple of more things for the feedback. I want to remind them to use the rubric to self-assess before they hand in the paper, and then mark their paper according to how close they think they are (I will use a technique called “traffic lighting,” where a student marks the paper green if they feel like they are close to done, yellow if they are in the middle, and red if they are stuck).

Thanks for the reminder, Joss! Bret

2. SBF « Solvable by Radicals Says:

[…] fact, once we do this, we are awfully close to Assessment FOR Learning…stuff (I needed a fourth word for my fourth link. The proper term is Assessment FOR […]