Sunday, February 26, 2017

Watching Student Understanding with EDpuzzle



In addition to teaching AP Biology in a traditional school, I also teach a Biology class at a homeschool consortium once a week. I only have these students for 90 minutes a week. I use that time to complete a lab--choosing them carefully to help support the content of the course that they are learning primarily at home.



We use a textbook and have weekly reading assignments with notes for them to complete.  I could tell though that students weren't always grasping the material they were reading about. I kept seeing tweets about EDpuzzle and decided to give it a try. I love it!



Before EDpuzzle, I regularly would assign them a video to watch along with their reading assignment, but there was no way for me to know if they actually watched it or if they understood.  With EDpuzzle, not only can I assign a video to watch, but I can add questions and comments throughout the video to emphasize important concepts and test their understanding.



Before class even begins, I am able to see who has watched the videos, how many times, and check their answers to the questions to get a picture of how well they are comprehending the material. Each student chose a user name and password and were enrolled in my class. Now I have a dashboard that allows me a quick overview of how the class is progressing.



EDpuzzle even integrates with Google Classroom. That doesn't help me for my consortium class, but if I wanted I could pull my AP Biology class in with one click.


There are 1000s of pre-made video lessons you could use if you don't want to make your own.

Sunday, February 19, 2017

Unit 8 Reading Guide-Plants


I've started to prepare for our next unit in AP Biology.  This is our shortest unit of the year.  We only take 8 periods for this unit--4 of which are spent on the Transpiration lab. The picture above was taken last year as part of this lab. I combine all of the plant chapters into one set of notes, since we primarily focus on transpiration and tropisms.

Here are the notes:

Guided Reading for Unit 8  

Saturday, February 18, 2017

Review and Teaching with Kahoot!



Over the summer, I saw several pins on Pinterest of teachers using Kahoot! I finally decided to check it out for myself. The school where I teach is a one-to-one iPad school, so each of my students has either an iPad or a cell phone--if their iPad happens to have a dead battery. I created a free account at getkahoot.com and gave it a whirl.  I found an AP Biology Kahoot on the first unit we study (there are over 14 million Kahoot!s already uploaded and available to use), and asked my daughter and husband to be my guinea pigs.  Even though they didn't know much of the content, they thought it was fun and I decided that I would try it out with my class this year. Students don't need an app or even a sign in. They just go to kahoot.it and enter the game pin that's up on the screen in the classroom.



I can't believe how much my class (12th graders) have loved Kahoot! Until this week, I have only used it for review before a test.  Still, the class has enjoyed it so much that they began persuading other teachers to give it a try. Their English teacher was convinced to try it and told me how much they enjoyed it in her class as well.  Two other teachers have come on board as well. One of my students is very reserved, so I knew she must really love Kahoot! when she saw we were playing that day and danced a little jig in the classroom.



Before midterms, we did one Kahoot! a day to prepare for the exam. One of my students suggested that we replay so they could reinforce what they were reminded of the first time. I tried to do this as much as we had time for. If I had thought about it, I could have shared a link to the Kahoot! with them so they could do it on their own when we ran out of time in class.



While we were doing these reviews, I saw the ability to download the results to my Google Drive. I loved all of the information it gave me and was also helpful because I had offered incentives for student earning certain scores.



This week I decided to try a Blind Kahoot! Instead of being review, I wrote a Kahoot! to help introduce our new topic. I was even able to add an instructional video to one of the questions. They still loved it, but even more so when we got to the end and decided we would play again in ghost mode--where they are playing to beat their first score (their ghost).



They quickly learned that in ghost mode, the order of the answers are changed.  Their was quite an outcry when several students clicked the option location that was correct in the first round once they realized that the options had been scrambled. I loved it since it meant that they had to reread all of the options to make sure they were choosing the answer they really wanted.



Here's the link to the Blind Kahoot! we did this week.

Thursday, February 16, 2017

Transcription and Translation Modeling in Biology

4 different already "Unzipped" DNA strands 


When deciding what we'd do in class to help students understand the process of transcription and translation several blog posts gave me inspiration.  I had just done the transcription translation lab from Kim Foglia in AP Bio and I read these posts on making proteins out of beads on the Science Matters blog. Inspiration struck to combine these two labs into one for my class.

RNA nucleotides ready for transcription


I started the process backwards, by deciding which amino acids would be in the finished proteins. Since the pack of beads I already had at home only had 7 different colors, there were only 7 types of amino acids in our proteins. Two of the designed proteins were identical. I wanted students to be able to see that two strands of mRNA with different orders of nucleotides could produce the same protein because there are multiple codons that code for the same amino acid.  The visual also helps during discussions of silent mutations.

Using DNA as the template for transcription


Next, I wrote the mRNA code for each protein, making sure that I used different codons for the amino acids in the matching proteins. Then I wrote the DNA code that would be transcribed into our mRNA strands.  I felt a little like reverse transcriptase as this point! Now that I had all of the codes I wanted, it was time to prepare the model materials,



I made the beaded proteins and labeled them with a number and set them aside as an answer key for students to check when they were finished. I used a sheet of DNA molecules from Biology Corner, and used the RNA nucleotides from Kim Foglia's lab.  I color coded each DNA nucleotide we would use in the lab, laminated them, and lined them up in the correct order for each of the 4 DNA strands that we would start with in the lab. I taped the line of DNA together with two long strips of packing tape-one on the front and one on the back.  I wanted to make sure it was super sturdy since I wanted it to last for several years (OK, true confession, I want them to last forever). This was time consuming, but hopefully won't need to be repeated any time soon (unless someday I have a class with more than 4 lab groups).

Amino acids ready for translation


Kim Foglia's RNA nucleotides fit perfectly with the DNA from Biology Corner, so I printed each type of nucleotide on a different color paper and laminated them before cutting them all out. These I just put in containers for students to take as they are modeling the process of transcription as they build their mRNA molecule.  Since each RNA nucleotide (A, C, G, and U) is a different color, it's easy for us to hold each lab groups' finished mRNA molecules together to compare them.



After they finish transcribing their mRNA molecules, students move onto translating the mRNA code into a protein. Once the proteins are made, we can compare them. We focus on protein 1 and 4, which match. Then we go back to the mRNA molecules and observe that they are not the same.  At this point we can look at the codon chart, talk about multiple codons for the same amino acid, and what it means to have a silent mutation.

Comparing mRNA from strand 1 and 4 since they built identical proteins 


Here's the link to the student lab. And here's the link to the lists of DNA, mRNA, and protein strands.


Tuesday, February 14, 2017

Visualizing Real DNA and a Model



For my high school level Biology activity dealing with DNA, we complete it in two parts.  First we look at real DNA--a lot of it, so we can actually see it, Then we build a model of it--including the beginning of replicating it.

We begin with extracting DNA from strawberries. Commercially grown strawberries are octoploid (have 8 sets of chromosomes instead of the normal 2).  We talk about what we need to get through to get to the DNA in strawberry cells, and relate it to each part of the procedure.  We mash the strawberries in a bag to break the cell walls, we add some soap to get through the phospholipid membranes of both the cell membrane and nuclear envelope, and salt to help separate some proteins from the DNA and keep them from precipitation out with the DNA.



This year, to separate the juice of the strawberries from the leftover pulp, I cut up flour sack towels. This worked better than the cheesecloth we used last year which let some pulp through. With the flour sack material, students were actually able to squeeze the juice through the towel and into their beaker.



Then students poured the juice into a test tube.  With the test tube held at an angle, they slowly poured ice cold rubbing alcohol into the test tube.  The hope was not to actually mix the two liquids, but form a layer of rubbing alcohol on the top.  The cold alcohol pulls the DNA that is dissolved in the juice out of solution and into the alcohol. Then students see the clear/cloudy with some bubbles come out of the strawberry juice into the rubbing alcohol.



As we're waiting the 15 minutes to allow the maximum amount of DNA to come into the alcohol layer, we begin on creating a model of DNA and then a model of DNA replication.  This is done with licorice, gummy bears, and toothpicks.  One thing I'd like to do differently next time is change to a different color of licorice for the part we are replicating to allow for a discussion of semi-conservative replication.



Here is the student handout for the lab.   The extraction buffer recipe was from this document. I used the 50 mL of dishwasher detergent this year, but last year I used dish washing detergent (way too many bubbles!). I don't have that many lab groups, so 1 liter of extraction buffer was far more than I needed.  Next time I'll use 25 mL of dishwasher detergent, 1 tsp. of salt, brought to 500 mL with water.


Monday, February 6, 2017

Hardy-Weinberg Population Modeling Lab for AP Bio


I decided that this year, we would bite the bullet and do the AP Biology mathematical modeling lab for populations.  Last year I found a YouTube video of a teacher explaining how to set up the spreadsheet to start the lab.  He did a nice job of explaining what the formulas that students would need to use meant.  For his class, they used Excel, but we generally use Sheets in our class.



I was stoked to see a new resource this December in the College Board AP Biology Community. This resource, done by Brittany Franckowiak was step by step instructions for students to set up a population in Sheets that was in Hardy-Weinberg equilibrium.  Then students are set free to figure out formulas to represent populations that are exhibiting heterozygote advantage, fatal recessive, or small population size (genetic drift).

When I'm doing a lab for the first time, I like to do it myself before I ask my students to. It was easy to follow the step by step directions to create the 5 generations of populations in Hardy-Weinberg Equilibrium.

Then I started thinking about how to represent heterozygote advantage.  In the card based Hardy-Weinberg lab we did last year, for heterozygote advantage we tossed a coin when a homozygous individual was born.  If the coin was heads, they lived, tails, they died.  In the first part of the mathematical model we create, we used an "if" function with the "random" function. I decided that I could add an extra "if" and "random" function to the existing "if" statement that counted homozygous genotypes of zygotes. It would act like a coin toss to decide if the individual would survive or not.

I excitedly shared my newly created formula with my computer programmer husband who regularly manages spreadsheets with a million rows or more.  He gave me a further suggestion.  My formula is done with the assumption that homozygous individuals have a 50% chance of survival, but I can change rand()>=0.5 to rand()>=0.3 if they have a 70% chance of survival (or a 30% chance of dying). I could adjust that number to match whatever a known survival rate is.  I loved this suggestion, although I'm not sure if my students will get that far.  I don't plan to share my formula with them, since I want them to figure out a way to model heterozygote advantage themselves.

Fatal recessive and small population size should be a little easier for them to figure out how to model. I may offer some incentives to encourage them to stick with determining how to model the heterozygote advantage.

I only made a few changes to the document by Brittany Franckowiak and it's here. Also, here is the sample Google Sheet I was working on.  In my sample, I added an additional tab to show heterozygote advantage, but I will have my students make a copy of their original sheet and then modify it for different scenarios.  Keeping it all in one sheet makes A LOT of rows to update every time someone makes a change and can be slow going.