Biology by the Math Mom: July 2020

Two years ago, I heard about the Tomatosphere project and applied for my classes to participate. The First the Seed Foundation sent us two packs of seeds, each marked with a different letter. One of the packs of tomato seeds has spent 6 weeks on the International Space Station and the other pack has never left Earth. We don't know which is which until we submit our germination results.

My classes plant the seeds during the first unit of the year. We're talking about distinguishing living vs. non-living. We start the class with a Do Now from Uncovering Student Ideas in Life Science, Volume 1: 25 New Formative Assessment Probes by Page D. Keeley. The assessment asks students to explain their thinking about whether a packet of tomato seeds is living or not. After some discussion, we work on planting the seeds. I post these directions as they work on planting the seeds.

This is a great lab to do at the start of the year, as it allows us to talk about control groups (seeds that didn't leave earth) and blind trials to prevent bias or unequal treatment between the two groups. We also work on hypothesis development as I have them decide which seeds they think will germinate best and why. This allows us to emphasize that an experiment is not a failure if the hypothesis is not supported. At the conclusion we begin to introduce the idea of statistical significance as well.

The first year I did this with my Honors Biology class, they were so invested in these seeds that when I revealed which seeds had been in space, they actually cheered. That first year, I also had my AP Biology class work with the seeds, but the focus was not just on being in space or not, but also on other factors that may affect germination rates. We germinated the seeds on paper towels in petri dishes. Looking back now, I find planting them in cups of dirt more satisfying.

Last year our germination rates were much lower than the year before. I'm not sure why. It'll be interesting to see the germination rates this fall. I'm hoping that I'll have my students in person long enough to get them planted, then if we have to go virtual, I can just have them bring their cups of planted seeds home and continue the observation from home.

Since I returned to the classroom five years ago, I've been having my AP Bio students practice released Free Response Questions from past exams. In the last two years, I've been coupling that with having them grade not only their own responses with the scoring guide, but scoring the student examples that the College Board provides. My students have said that they find this exercise helpful, so I continued this practice even when we were online.

Doing this online posed a few challenges. I didn't want to have to post a bunch of documents (questions, rubric, and student samples) and I didn't want students to see what the actual scores of the samples were. The longer I was teaching from home, the more ways I figured out how to solve these problems.

One way was to print out the pages I wanted and then used the Image Capture app in my school MacBook to scan all of the documents on my wireless printer/scanner into one PDF. I didn't even know I had this app until I found it by accident in desperation while online teaching. My daughter, who was zooming for college, was delighted that I found this. She regularly had to scan documents and upload them for her classes. One benefit of this method is that I could mark out the letters that the College Board had put at the top of the student sample FRQs and put my own letters on them. This is handy because my students quickly figure out that the A example is the best score, B is in the middle, and C is the worst. This method allowed me to just provide students with the original FRQ, the scoring guide, and the three student samples. When they were finished I would then reveal what the actual scores of the student samples were. (Which is what I usually do in the classroom.)

I wasn't keen on printing out that many pages...especially since I knew printouts were sitting at school. The second way I figured out how to take pages from several documents and put them into one was using Notability. I put all of the separate documents into one document in Notability, eliminated the pages I didn't want, and changed the order of the student sample pages. I could also mark out the original letters marking the student samples and add my own.

To keep all students participating even if they are reluctant to share in class or on Zoom, I put together this Google Form for them to report their results in. In the classroom, I'm able to walk around and check on the progress of each student. This was much harder online. And both online and in class there are always students more reluctant to share. Filling out the form allows all students to contribute without putting any of them on the spot.

Here are the FRQs that I've done so far. They are primarily from ecology and human body systems since those are the last two units of the year. I only changed the order and letters of the first question linked here, since this Spring I was working in survival mode and was just trying to get the documents workable.

Human Body Systems

Ecology