Excerpts from AP Biology Teachers Discussion Group
Tip: "Here is a simple hands-on activity for protein structure. I buy curling ribbon in our two school colors. Each student gets one 10-12 inch piece. The ridges on the ribbon represent each amino acid. Demonstrate how to curl the ribbon and have the students do it to get a helix (the secondary structure). Folding the helix back on itself into a glob makes the tertiary structure. And combining two or more different colors of ribbon shows them a quaternary structure. What I like about this activity is that the kids are actually doing it themselves instead of just watching me do it all."
-- Tricia Glidewell, Marist School Atlanta, Georgia. 2/13/99
Tip: "For hydrolysis and dehydration synthesis: I ask a group of volunteers to play 'choo-choo,' each with his or her hands on the shoulders of the person ahead. As they walk around, I mention how much fun it is to relive the carefree days of elementary recess. I also make a great show of putting water into a bucket (in reality, I only put in about a tablespoon full or two). Suddenly I yell, 'Watch Out!' and pretend to throw the bucket of water at the train. The students inevitably scatter. Then I say, 'The water is gone, you can reform the train.' After they have done this, I talk about how a carbohydrate is like a train, a string of monosaccharides. When I added water, the train broke up. When the water was taken away, the 'train' reformed. I go over the derivation of the terms, hydrolysis and dehydration synthesis. Students tell me that this demonstration is one of the things they remember most years later.
For protein structure, I give each student a strip of paper. On it, I have them draw a string of amino acids, referring back to the cars of a train idea. I point out that it is easy to tell a tank car from a boxcar, yet they must have a commonality in order to be part of a train. Then I have the students pleat the strip to demonstrate secondary structure and coil the pleat to demonstrate tertiary structure, pointing out that releasing the strip causes the coil to open. Something must be 'gluing' it in position. We talk about disulfide bridges. We also talk about denaturing proteins. Last I have them recoil their pleated strip and nestle their strip into a group made of the strips of three nearby students to simulate quaternary structure. Students may staple their strip onto their notes to rebuild the protein when reviewing."
-- Margery Weitkamp, James Monroe High School, North Hills, California. 2/13/99
Question: "Does anyone know where to purchase biology games? Biology bingo? Biology trivial pursuit? Computer games about biology? Fun things that students might come do on their own time?"
Answer: "You might check Ward's or Carolina Biological for games. Or, I have seen other teachers (very successfully) give assignments to have students adapt a game such as Life or Monopoly or another game to a science game -- the creativity of students can be incredible. I have used DNA bingo very successfully -- it is very simple to put together: game boards with blank squares. Have the students write the names of the aa's on a 5 x 5 grid, leaving the middle square as a freebie. Also have pieces of paper with codons to pull from a sac. There are both RNA and DNA codons, which will make the students work a little harder. I use this the week before the AP as a fun way to review! This activity came from the 1994 Woodrow Wilson Bio Institute, by Cynthia Mannix. Many of the Woodrow Wilson Institute Modules have games in them."
-- Franklin M. Bell, St. Mary's Hall, San Antonio, Texas. 4/26/99
Question: "Does anyone have any good ideas for introducing the Scientific Method?"
Answer: "Here are two activities that I used in AP Biology that were very popular with students but I am doing this 'off the cuff.'
Ear Candling. (Students have told me that this one was the best, but word got around the school about it so I will have to wait a few more years to do it again. It has to be a surprise to be effective.) I have found that many people have never heard of this (which is one of the reasons why students were so fascinated with it). I set this up for the first day of class. I bought ear candles at a health food store. I bought enough candles to do one demo and one for each lab group. I went to this site and printed out a copy of the ear candling procedure for each student. I brought in a towel, a plate, etc., and an old photo of myself showing my mother candling my ear (an old 'Italian' thing that my mother swore by). I put on my lab coat, wet the towel, and gave the steps on how to do this to several students that I trusted and had them candle my ear. (I had them do only one ear.) I was very 'serious' -- there was no hint of a smile on my face but inside I was having a lot of fun! Students, of course, were very grossed out that they were going to be removing ear wax from their teacher's ear. I sat in a student desk and put my head on a pillow, and my trusted students followed the directions and candled my ear. I had them stop when the candle was about halfway burned. I took the candle out of my ear, put it in a pan, and sliced it open with a scalpel. They were amazed at the amount of 'ear wax' that came out of my ear. I told them I had not done it for a while and was glad to have the wax out of my ear. I saved my 'ear wax' candle.
I then showed students price lists from the Internet. Some places charge 50 to 75 dollars per ear. I divided them into groups, gave them one ear candle, and told them their assignment was to prove or disprove what they had just observed. They were allowed to use any lab equipment that they needed as long as they passed it by me first, BUT THEY WERE NOT ALLOWED TO CANDLE ANYONE'S EAR. They had to come up with, and carry out, an experimental design.
Believe me, some of their experiments were unbelievable. I had all kinds of fatty substances around that they could use to simulate ear wax, such as paste car wax, Crisco, and liquid vegetable oils. I had one group use a narrow test tube to simulate an ear canal, used car wax, a ring stand , etc. They sealed their candle to the top of the tube after carefully measuring the gram weight of the wax. Then they lit the ear candle. When it had burned down as much as 'my' candle, they stopped and opened up their candle and compared it to mine. They weighed the car wax left in their test tube and the wax that was in their candle. Something was wrong with the data. I let them struggle with in for a while. No one could figure it out. (Of course the reason for this was that they had bought into this 100 percent -- they were convinced that they had seen ear wax in my candle.) Finally I had them go on this site... of course ear candling is a hoax. We had a very good discussion about the scientific method and bias. It worked because they were so duped by the demonstration. They questioned everything after this and it was a fun semester for me. I know this is a little crazy but it worked well for me.
Chitosan. (I did this one last semester) I bought a bottle of Chitosan tablets (advertised as a 'fat absorber' to help you lose weight) at the health food store. I had the students spend a period researching chitin, its chemical structure, etc., and also researching the process of how Chitosan is made. Also, I had them research fat absorbing properties of Chitosan... and had them look for reliable data (there are many sites on the Internet about this). They had to look for negatives about Chitosan (which seems to also block vitamin absorption and antibiotic absorption).
Students formed lab groups and designed experiments to test the fat absorption properties of Chitosan. They used mortars and pestles to grind up the Chitosan tablets and designed lab protocols to test. I brought in the cheapest, fattiest bacon that I could find and cooked the bacon to draw off the saturated fat. We used bacon fat as our fat source. An added bonus... the lab smelled great and lots of teachers in my hall had their breakfast! It is actually very easy to see Chitosan work. If you float some salad oil in water and then add Chitosan, it will clump up the oil. My students were trying to determine the amount of fat it absorbs and compare this to advertised claims. Several lab groups also tried to test for vitamin and antibiotic clumping. Finally, I had students go on the Internet to read about a Westinghouse Science Fair top-prize winner that worked with Chitosan to absorb oil slicks. This was a good introduction to the scientific method and the students learned a lot about the chemical structure of chitin."
-- Sandra M. Ivey, Bangor Area Senior High School, Bangor, Pennsylvania. 8/11/00
Question: "My school requires that we have one day of emergency lesson plans on file in case we are unconscious or worse.¿ I was hoping someone in the Advanced Placement Program had a good general lesson that can be used independently by the students (as I will not be conscious) and would take up a good three-hour block of time. This lesson has to be able to be used at any time of the year... something that does not require the use of the lab or the
Answer 1: "I keep class sets of articles that I glean from various journals, such as Scientific American or Discover. I make up questions that cover the articles (they can be put on an overhead sheet so that the sub doesn't have to use the Xerox machine). If you use analysis- and synthesis-style questions, the students will need to think a bit more about the article and will take more time. The substitute teacher can pass out the articles, have the students read them quietly, and then put the questions on the overhead for the students to answer. You could also keep butcher paper on hand and ask the sub to have the students form groups and draw out a detailed concept map on the next chapter they will cover (or on the chapter they just covered). That way, the sub doesn't have to try to keep them quiet."
-- Jo Ann Burman, Andress High School, El Paso, Texas. 8/19/00
Answer 2: "Here's what you need to keep in mind: If you really were in such dire straits as to be unconscious, then there are more important things going on in your life than teaching AP Biology! Don't feel that the lesson the kids are doing has to be brilliant -- it just has to be relevant. Your ecology idea is good. I would search the video library for a good ecology video to introduce some desired topic (which should be about 30 minutes in length) and write some thoughtful questions for it. Then find a pretty challenging article from Scientific American, e.g., one that develops the topic but will require some work if the kids are to understand it. Develop good questions for the article. Give the students time to read the article and answer questions. If there is still time in class, have the students form groups to go over the answers. In an AP class, your students should be pretty good at teaching themselves with minimal guidance from a sub. Also remember -- with any luck, you will never need to use this lesson!"
-- Leslie Haines, Walter Williams High School, Burlington, North Carolina. 8/20/00
Answer 3: "All the emergency ideas I've seen posted (articles, video) sound great. Perhaps some day you will have an emergency situation where the kids will have to unexpectedly fill in for themselves, or perhaps, the office will have trouble finding the official plan for some reason. If that happens, from the beginning tell the class that there is an emergency lesson they can always fall back on. Have them divide themselves into groups of three or four. They need to divvy up the current chapter they are working on. Each individual should take a separate page, read it, think up one or two questions and write them down. The group should read the whole set of three to four pages and then trade the question sheets around, writing their answers on the sheet and passing it to the next person. Each new recipient needs to add at least one sentence to the answer. When those pages are done, they can discuss and look up the text information, then do the next three or four pages the same way. My students found this technique very helpful, especially as a test review."
-- Margie Weitkamp, James Monroe High School, North Hills, California. 8/20/00
Answer 4: "I keep a sample of essay questions from past exams on topics that we have already covered -- the students work in groups of three or four and use no book or notes (just one another) to answer the questions. Everyone writes it up, but only one paper, which has all the names in the group, is turned in, and they all get the same grade. I have found that of all the in-class assignments I give, the students surprisingly like to do this and, with the interaction, they seem to get a lot out of it. I do this sometimes even when I am present because it breaks things up (they are also pretty quiet, because they don't want the other groups to hear them discussing the answers!)"
-- Linda Curley, Pittsfield High School, Pittsfield, Massachusetts. 8/20/00
Answer 5: "A Nova presentation that you would not normally have time for in class might work. Nova's guidebook would allow you to have a printed introduction plus some follow-up questions. It might not take three hours."
-- Carl Koch, Riverside Brookfield High School, Riverside, Illinois. 8/21/00
Question: "Does anyone know of a good mark-recapture activity?"
Answer 1: "We use goldfish crackers -- lots of the regular, cheddar type (about 200 or more per group). They 'capture' a small cupful, count them, and then replace them with another 'marked' type (we like pretzels for this). (We did not like the idea of marking things that students might consume with ink.) The original, counted goldfish can be consumed at this point. Then they capture another small cupful and count both the regular and the marked ones. They return these to the larger population after recording the counts. This is repeated for a total of five trials. The averages are used in a proportion equation to estimate the total population. It has worked well for us."
-- Ellen Mayo, Mills Godwin Specialty Center, Virginia. 9/9/00
Answer 2: "I would highly recommend Doris Helms' lab manual, Biology in the Laboratory. It has some excellent labs. I use her predator-prey lab as an ecology lab. I also have a lab called 'Tragedy of the Commons,' which I got at the Indiana University AP Biology workshop. It is about fishing and overexploitation and uses goldfish crackers. My big ecology lab is to go to our local creek and the town's water source and do water quality testing."
-- Barbara Burkhardt, Zionsville Community High School, Zionsville, Indiana. 9/9/00
Answer 3: "If you would like to be involved in a long-term mark-and-recapture project, consider the Monarch Watch. The monarchs are tagged in the fall and the following spring, and the groups publish a list of all recoveries. A great project although we have yet to have one recovered."
-- Carl Koch, Riverside Brookfield High School, Riverside, Illinois. 9/10/00
Answer 4: "Mark-Recapture Lab (Measuring School Population Size). In my morning intro biology class, students capture other students they find wandering the halls. They record data such as name, grade, time, and location of capture. Then they mark them by tying a piece of yarn around their wrists. My afternoon period takes shifts monitoring the hallways and capturing more wandering students. Again they record the above information and then put an 'X' on their hand to indicate that they have been recaptured (in case they were to be caught again). Recording student names is useful in case the yarn is removed. That makes for a good 'lost tag' discussion. Of course this lab violates many of the assumptions of the Mark-Recapture Method, but the students do a great job in identifying them and redesigning the experiment to get accurate results. A bonus for our dean of students is a list of students who frequent the halls. My kids thought it was great and they loved capturing their friends."
-- Heather Roffey, Smith Academy, Massachusetts. 9/11/00
Answer 5: "The source for the Tragedy of the Commons lab is Hand-On Biology: A Lab Manual for Introductory Biology by Theodore Taigen, Thomas Terry, David Wagner, and Eileen Jokinen. The publisher is McGraw-Hill, the copyright date of the one I use is 1991, and the ISBN is 0-07-050642-6. The Tragedy of the Commons lab is under the Environmental Biology section. It is a good lab book for basic labs. I still would highly recommend Doris Helms Biology in the Laboratory Manual as a must have for all AP Biology teachers. W. H. Freeman is the publisher. I use the 3rd edition (ISBN 0-7167-3146-0). It also comes with an instructor's manual as a separate item (ISBN 0-7167-3237-8), which is needed because it lists all the materials, solutions, etc. needed for the lab. It also has an answer guide (ISBN 0-7167-3236-X)."
-- Barbara Burkhardt, Zionsville Community High School, Zionsville, Indiana. 9/11/00
Question: "Does anyone have any good molecular model kits they can recommend?"
Answer 1: "Prentice Hall molecular model kits are outstanding. The students love them and they are very durable. They can be purchased directly from Prentice Hall, which eliminates the middle-man cost of using a supply house such as Carolina, etc. The ISBN is 0-205-08136-3. The kits are called The Prentice Hall Molecular Model Set for Organic Chemistry. They are made in England by a company called Molymod. You can contact your sales rep for a sample kit and additional information. When I purchased them about two or three years ago, the cost was $33/kit."
-- Marcia Fischer, Desert Mountain High School, Scottsdale, Arizona. 5/19/01
Answer 2: "Cochranes of Oxford molecular model kits... awesome kits. You can buy kits or the pieces and build your own. Cochranes of Oxford has a Web site, which is listed under "See also" and their other contact information is as follows: telephone: 01-993-878641, Cochranes of Oxford, Leafield, Witney, Oxon OX8 5NY, United Kingdom, email@example.com. I use these same kits every year to introduce organic molecules. You can find the worksheet, Franklin Bell's Worksheet, which I give to the students when we start under "More." I give one lecture to introduce the molecules, and then we build for about two days. I have them start by building glucose, then we build a disaccharide, and then we put all of the disaccharides together into a polysaccharide. Same for the protein. I have each one build an aa, then put two of them together to make a dipeptide, and then put them all together to make a polypeptide. Be sure you have two cysteins so you can demonstrate a disulfide bridge in the tertiary structure. I find that after building these models the students really understand the molecules much better than if they just look at pictures in the book."
-- Franklin Bell, St. Mary's Hall, San Antonio, Texas.10/23/00
Question: "How do you handle taxonomy quickly and efficiently?"
Answer 1: "I am also searching for a new way to cover the kingdoms. I don't want to bore them with lectures on the various kingdoms and phyla. I plan on having them present the information. I have seven students and figure each student can research one invertebrate phyla and one vertebrate phyla and do a power point presentation on what they find. I am collecting ideas from a variety of sources. "
-- Pebble Barbero, Highland Park High School, Dallas, Texas. 2/9/01
Answer 2: "I bring in live organisms, including bacteria, protists, fungi, plant, and animal (one species each for each team of three students or so), not telling them anything about any of the organisms, labeling them A, B, C, D, and E in random order. They must work together for about two or three class periods (and in some cases extra time out of class), 'keying them out' and preparing an oral presentation on each for the class. They must be able to present criteria for the classifications that they decided on for each. I try to choose a representative diversity among all of the organisms I provide for the class. They also get microscope practice in the interim. I am there to facilitate any investigations that they wish to conduct to test their hypothesis for identification, but I try not to lead them too much. We usually do not have time for each team to present all of their organisms formally to the whole class, especially the prokaryotic species. But that's okay; I make sure that all major phyla/divisions are represented. I usually do this as a course opener to get to know the students and to provide the more concrete thinkers with something to 'get their hands on' and 'get their feet wet' early on -- something to which they refer throughout the year as we get increasingly molecular/cellular. It works really well. They get VERY engaged in the subject, enjoy the unit a lot, and learn quite a bit. In summary, we spend two to three days in the lab, plus one day or so of quick class presentations (drawing lots out of a hat for order of presentations), then a final day or two for me to sum up everything and fill in critical gaps. We have a taxonomy test at the end of it all. They have copious amounts of reading in the interim -- all of the survey chapters from Campbell, including AT LEAST an overview of each major group, diagrams/tables/photographs, and chapter summaries."
-- Barbara Beitch, Hamden Hall Country Day School, Hamden, Connecticut. 2/9/01
Tip: "Through The Biology Place Web site (a subscription site) there is a link to a site titled, 'Introduction to the Eukaryota.' The link is very good and I used it as a secondary source of information. There are excellent descriptions and photographs of each major phyla. It is not organized in the same manner as Campbell, but if you look, you will find all the phyla. Try typing the above title into a search engine and see what comes up."
-- Patrick Foley, Avon Old Farms School, Avon, Connecticut. 2/9/01
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