October 30, 2011
Happy Halloween, everyone! We had a really busy week in class this week. The campaign projects turned out great! There are some really creative students in my classes this year!
Events of the Past Week
Monday - Monday was our first day of presentations. The first 10-15 minutes of class were spent passing out flyers and campaign extras to try and earn people's votes! Then we began presentations on each organelle. We made it through about six presentations in each class. Obviously, I underestimated how long the presentations would take, so plans had to be adjusted for the rest of the week. Most of the presentations were very strong both factually and creatively. The groups did an outstanding job learning the functions of their individual organelles.
Tuesday - Tuesday the last 7-8 groups gave their presentations. This took the full class period in most classes. For those that it didn't take all period, the students were able to move around the room and look at everyone's campaign flyers and smear campaigns. There were some excellent smears against organelles such as the nucleus (i.e. "Do you really want a control freak telling you what to do?" and "Just another in a long line of dictators").
Wednesday - On Wednesday I was at the administrative building working with a group of Fremd teachers looking at ACT data and enrollment in accelerated and AP class data. As a result, the students were given a lot of review material to work through. There was a matching review sheet, a crossword puzzle, a short answer and multiple choice review sheet, cell diagrams to label, and Venn diagrams to complete comparing plant and animal cells as well as prokaryotic and eukaryotic cells. My student intern in fifth hour ran a flyswatter review game. If you have a child in my 5th hour class, you can ask them to explain how the review worked. Most of the kids really liked it!
Thursday - We began class by voting on the most important organelle in the cell. There was a poll on my website for each class to use to vote. The students were allowed two votes. One was a vote for their own organelle, and the other was a vote for somebody else's organelle. The winners were:
1st Hour - The Ribosome - Matt Cheng and Nathan Cornwell
2nd Hour - The Vacuole - Gina Pfister and Reilly Siepka
3rd Hour - The Mitochondria - Will Lefevre and John Thiel
5th Hour - The Lysosome - Elizabeth Chick and Dan Pinderski
Particularly impressive from that list of winners were the vacuole and the lysosome. The vacuole simply stores water and nutrients, so to convince people to vote for them, Gina and Reilly did an outstanding job on their project. Also, the lysosome was smeared by almost every group because it destroys worn out organelles. It can also rupture and destroy the entire cell. This, of course, made it an easy target, but Elizabeth and Dan did a great job of convincing people to vote for them.
After voting was completed, we took time to look at each review activity the students had completed the day before, and I answered any questions that they had about the review activities or organelles in general.
Friday - This was quiz day. I was anxious to see how the students would do after the project. Since this was the first time doing the project, I wasn't sure whether or not it was going to be an effective way for them to learn the material until there was actually some proof. I had the sense that they had learned the organelle functions well, and they seemed to enjoy the project, but the proof would be in the pudding. The class averages on the quiz were:
1st Hour - 23.4 out of 25
2nd Hour - 22.8 out of 25
3rd Hour - 23.1 out of 25
5th Hour - 23 out of 25
The quiz itself was 50 multiple choice and matching questions about the cell organelles, plant and animal cells, and prokaryotic and eukaryotic cells. Each question was worth half of a point. The results show that most students only missed around four questions out of fifty, which I consider to be outstanding. As a result, this is a project that will probably be continued in the future.
After everyone was finished with the quiz, we began one of several lab experiments we will be doing to investigate how materials move into and out of cells. The lab we began will be completed over several days. Day one involved measuring 150 mL of vinegar, taking the mass of an egg, placing the egg in a plastic cup, and pouring the vinegar over the egg. The eggs will sit in the plastic cup over the weekend, and we will come back to look at them on Monday. Does anyone know what will happen to the egg while it sits in the vinegar?
Monday - We will take our eggs out of their cups and take their mass. We will also measure the amount of vinegar remaining in the cup, then rinse the cups, put the eggs back into the cups, and add 150 mL of deionized water to them. When this is completed (it should take about 10-15 minutes), we will begin our next activity.
One activity we did not get to before the quiz that I would still like to have the students do is look at plant and animal cells underneath the microscope. They will look at cheek cells, onion skin cells, and elodea (a green aquatic plant sold as Anachris in pet stores). They should be able to observe plasma membranes, nuclei, nucleoli, cell walls, chloroplasts, and central vacuoles in this lab. This will be what we do after the egg lab at the beginning of class.
Tuesday - We will again begin class by taking the mass of our eggs and measuring the amount of deionized water left in the cups. Then we will put the eggs back in the cups and add 150 mL of corn syrup to the cups.
After setting this portion of the lab up, we will first finish looking at the onion and elodea. Then I will begin lecturing to the students about the structure of the plasma membrane, diffusion, osmosis, and facilitated diffusion. If there is time, I will do a demonstration with ammonium hydroxide, water, and phenolphthalein (an indicator that turns pink in the presence of a base).
Wednesday - The final day of our egg lab will involve carefully drying the outside of the egg, taking its mass, and measuring the amount of corn syrup in the plastic cup. Students will complete the questions in the lab for homework.
Once this is complete, I will finish lecturing on passive transport and active transport.
Then the students will be looking at red onion cells under the microscope, first in deionized water, then with salt water added to them. The idea will be to look to see what happens to the central vacuole when the salt water is added. Students should notice it shrinks as the cell loses water.
Thursday - We will be doing a lab activity with a selectively permeable plastic bag that allows some materials to pass through it but not others. Small particles can pass through microscopic pores in the bag, while larger particles cannot. The students will be putting a solution of egg white, starch, and glucose into the bags. The bags will then be put in a beaker containing deionized water and let sit for about 15-20 minutes.
After 15-20 minutes of the bags sitting in the water, the students will test the contents of the solution in the beaker to see which nutrients were able to pass out of the bag, and which were not. They will run a benedict's test, a biuret test, and an iodine test on the contents of the beaker. It is always interesting to see who retains the information learned about these indicator tests during our biochemistry unit. Students should note that the glucose was able to pass out of the bag (because it is small enough), while the protein and starch were not able to pass out of the bag (because they are too big). They should also see that iodine enters the bag and causes the solution in the bag to turn purple as it reacts with the starch still in the bag.
Students will complete the questions in the lab experiments with the selectively permeable bags and the red onions. They will also observe two sets of vegetables that will have been soaked overnight. One will have been soaking in salt water, and the other in deionized water. The salt water vegetables should be very flimsy, while the deionized water vegetables will be extremely crisp. Your children should be able to explain why that is the case when they come home from school. I will then lecture on the topic of active transport. When that is completed, the students will be given a review packet on the topics of passive and active transport.
Friday - Students will be given a short, 10 question quiz on the topics of the structure of the cell membrane, passive transport, and active transport. After completing this activity, we will review everything we learned during our cell unit.
There will be long pieces of butcher paper on each lab table. Each piece of paper will have a different heading on it. The headings will be Cell Theory, Prokarytic Cells, Eukaryotic Cells, Plant Cells, Animal Cells, Passive Transport, and Active Transport. At each station will be colored pencils, and the students will be given 1 minute at each lab station to write down anything that they can think of about the topic on the paper. They will then move from table to table doing the same thing on each piece of paper. As they move, they can correct any mistakes they think they notice and add new material that they think is missing. Finally, students will be given 1-2 minutes at each station to go back around and look at each sheet again and see what was added after they left the station. We will then talk about what they observed and I will answer any questions that they have. Right now, the test on this unit is planned for Monday, November 7th.
Graba Geek of the Week
The Geek of the Week goes to the students whom I thought had the most creative and factually accurate smear campaigns. Ryan Moran and Matt Nicholson did an outstanding job with their smears, and for that, they have earned the Graba Geek of the Week. Congratulations, guys, and congratulations to all of my students who did an outstanding job with their projects. I was really impressed with the work that was done by these kids. The t-shirts, stickers, buttons, posters, websites, facebook pages, twitter accounts, food, and many other things that were created were really well done!