Natural Selection with Butterflies

One of the first labs I do with AP Bio in our Natural Selection unit, is this butterfly lab from Kim Foglia. I just converted her lab to a google doc and also have a google sheet linked to it where my students record their data. I like for them to be able to see everyone's data and to be able to compare.

The first year I did this lab, I collected some squares of cardboard and glued different fabrics on each. I think all but one of the fabrics were fat quarters. Then I used a standard hole punch to punch out 5 different colors of "butterflies." It was a little painful punching that many holes the first year, but I've gotten several years of use out of them since, so I guess it was worth it. For each of the fabrics, there is at least one color of "butterfly" that blends in incredibly well. Each environment will see a shift in the frequencies of different colors of butterflies, but it'll be different color shifts.

The students have enjoyed it each time we've done this lab and it gives a good picture of what is going on with natural selection.

Here is the link to the lab as a google doc. And here is the link to the google sheet I made for data collection. There are also links to this in the lab itself. Generally, I only print the last 4 pages of the lab for students and have them access the first three pages electronically through Google Classroom.

Using NOVA Labs Evolution Lab

Last week in Analytical Biology (Honors Bio), we began our Comparative Reproduction Unit. To get us doing some comparing, we did Mission 1 and Mission 2 of the NOVA Labs Evolution Lab. After watching a brief video and answering a few questions, students are off to building phylogenetic trees based on similarities and differences between different organisms.

The kids loved it, as it is set up more like a game than studying. I like that you can try out your tree and if it doesn't work (if dots fall off of the tree), you can readjust and try again. You can also click on the magnifying glass icon to get more information about the organisms you are trying to compare. This information is helpful for knowing how to put the tree together.

Although I only asked them to complete the first two missions, many students went on to the other missions--even though they covered topics that we haven't seen yet, namely DNA similarities to build trees. One student asked permission if she could complete all of the missions on her own. Of course!

One of the relationships they were surprised about was that a fungus was more closely related to animals than to plants. It led to some discussions about heterotrophs and autotrophs.

I set up a classroom in mypbslearningmedia.org and then could push out the assignment to my students through Google Classroom. The process isn't perfectly smooth, but all of my students found their way into the missions without too much help, and several students helped others to navigate their way in.

As students get further into the trees, they get more complicated. There is certainly some frustration as the trees get more difficult, but one student will figure it out and their celebration of figuring it out tends to encourage others to press on.

There are questions throughout to keep students focused on the learning that's happening. it also gives them an introduction to cladograms that they will have to interpret on the Regents exam in June, so that's another plus for this activity.

Pushing the Limits of the Electrophoresis Lab

For the second year now, we've been using Bio-Rad's forensic electrophoresis lab. My schedule is different than last year, so when I could prep for this lab had to be shifted. I poured the agarose gels on the Thursday of the week before we were going to do the lab and put them in the fridge with some buffer. I had planned to run the gels that Tuesday, so the gels would only be 5 days old.

I emailed the company about the feasibility of rehydrating the DNA samples and aliquoting them on Friday because I wasn't confident that I'd have enough time to do it Monday morning before we did the restriction digest. A Bio-Rad scientist confirmed that it would be fine.

Monday morning my students did the restriction enzyme digest. An hour later, we received the announcement that school would be closed on Tuesday because of how many students were out sick with the flu. On Tuesdays and Thursdays, we have 80 minutes for class, but on Wednesdays we only have 38 minutes. I knew 38 minutes wasn't long enough, so I called Bio-Rad and asked if our DNA would still be "runnable" if we waiting until Thursday. They confirmed that yes, it was possible and we could stick the samples in the freezer to be even safer.

Wouldn't you know it, we had a snow day on Thursday! Both Friday and Monday were only 38 minute periods for us, so I decided we'd just put it off until the next Tuesday. I figured even if it was a bust, I have pictures of successful gels and at least they would have the experience of filing the wells and watching the dye move through the gels as they were in the chambers.

The next Tuesday, 13 days after I had poured the gels and 9 days after we had done the restriction enzyme digest we ran our crime scene samples.

Although I followed Bio Rad's directions for running the gels in 20 minutes, I let them go for 45 minutes since the year before the bands hadn't moved very far. I think it's my power source. Anyway, by then my students had left for their next class, so I stained and destained their gels. I saw nothing right after. I figured the time lag was too long and I'd just show them pictures. I didn't toss the gels though since I wanted my students to see them anyway. I happened to take a look about 30 minutes later, and viola! There were the DNA bands. They weren't fabulous, but I think it has more to do with trying to run them rapidly. Next year I'll try the agarose concentrations for the longer running time and see how that goes.

Hands-On Law of Sines and Cosines

I love when teachers freely share ideas and materials online. Although I appreciate the work available in TPT (I use All Things Algebra's Precalculus curriculum and love it), freely shared resources are my favorite.

We were working on the Law of Sines and the Law of Cosines in class today and I was trying to decide what we would do for practice. This class is flipped, so my students had already done the notes.  Even doing a jigsaw with the homework questions seemed kind of dry. Happily, I found this lesson plan on the Utah Education Network.

I didn't do part one of the lesson, which was making a triangle reference model to give a concrete picture of which sides correlate to which angle, although given more time, it may have been wise to do it.

We did part 2 and started part 3 in class. We'll have to finish part 3 next class. Normally, we would have been able to get through part 2 and 3 in one 80 minute period, but we had a quiz and went over it, so the 60ish minutes we had wasn't quite long enough.

I love the hands-on aspect of this lesson--that students are using the Law of Sines and Cosines to find the missing information in the triangle and then actually measuring with rulers and protractors to verify. When we moved onto part 3 I handed out half sheets of tablet paper and several of my students were working hard to make the hardest triangle to solve--as in with the smallest angle possible for one of the vertices. We had just made it to the part of the lesson where students give their constructed triangles with three measurements to other groups to solve when we ran out of time.  Ideally, if students are choosing three different measurements differently for each of their constructed triangles, the students solving them should get an assortment of Law of Sines and Cosines practice.