Wednesday, September 03, 2008

AP Biology: Opening Day -- The Great Toll House Cookie Challenge

I decided on a new opening activity this year. I got the idea from a share session with other teachers at a Cornell (CIBT) workshop I attended this summer. I think it specifically came from Christine Courtsunis.

THE GREAT TOLL HOUSE COOKIE CHALLENGE!
Lab work & experimental design is much like cooking and following a recipe, so I decided we should bake cookies on the first day... but only as an analogy to experimental design. I baked a batch at home using the Toll House Cookie recipe from the Nestle's semi-sweet chocolate chip package. I followed the recipe to the letter -- which for me is REALLY difficult, since I am one of those cooks who modifies as she goes! Now my batch served as the original "experimental result" and the recipe was the experimental design. Now it was the students turn. I threw down the gauntlet -- can you bake cookies just like mine by following the recipe as well. I brought in a wide range of supplies:
  • different flours (but all were called "All Purpose" like the recipe called for
  • 2 different brown sugars (light & dark)
  • 2 different kinds of nuts (pecans & walnuts)
  • 2 different salts (Kosher/non-iodized & iodized)
  • 2 different butters (salted & unsalted)
  • 2 different sizes of eggs (medium & X-large)
Then the students were put to the task of making their cookies.
I had made prior arrangement with the Home Ec. department to be able to bake the cookies in their ovens once we were done mixing in our room.

Well, I am not sure what the students learned (yet), but I certainly got an interesting education in the end! Well, I envisioned students pondering whether to use light or dark brown sugar or salted vs. sweet butter and then asking me which one and I had my answer ready "What does the recipe say?" Because, in fact, the recipe doesn't specify... it only says butter. So this would blossom into a lesson of specificity of experimental design descriptions and the unexpected effect of unintended confounding variables.

Aaaah.... all the best laid plans of science teachers gone aft agley...

I quickly learned that students had little experience following recipes and had no clue how to proceed correctly. Yes, they dove right in, but I had groups just adding ingredients to each other as they were listed in the ingredient list or in random order -- not based on the instructions. So I saw butter and flour mixed together first... or butter and egg mixed together first... or all ingredients poured into one bowl and then finally mixed! Yeeesh!

So we now have to move this into a discussion of how to actually FOLLOW DIRECTIONS if you want to be successful in AP Biology.

Now, in all fairness, I think I created some of this situation by talking too long in the first period and rushing them into starting this. An approach that I will correct for next year. But I still had one group of young women who followed the recipe to the letter and even finished before everyone else.

I do have to remember to STOP adding the rush factor with any of my activities!

So tomorrow I am going to try to resurrect this lesson from the cookie crumbs and see if we can talk about variables. Then onto real hypothesis development.

FOLLOW UP
Next day -- lesson resurrection day...
I started off by explaining what my goal had been for the lesson of the previous day and then quickly segued into what I learned. I elicited from students descriptions of how they had not followed directions (procedures) and how they could have improved. It actually was a great discussion -- they can be prompted to get it!

We baked our cookies (we had to refrigerate them overnight because of lack of time) and then sampled across groups. It was amazing the variation in results we found from crispy flat cookies to cake-like puffed up cookies. This gave me the opportunity to compare to unwanted variations in experiments and then introduce the concept of confounding variables. I think we will be able to build on this foundation throughout the year!

And we gotto eat chocolate chip cookies, ta'boot!
And while munching we started to learn about the nature of science and generating hypotheses... more on that later.

I will definitely use again!

Thursday, September 06, 2007

Textbooks and Work loads...

How much work should students expect in AP Biology?
I tell students to plan on 1 hour per night.

I find that the biggest challenge is to get students to open up the dang textbook and read it! To that end, I switched last year from Campbell & Reece to Raven & Johnson. Yes, I know Campbell is commonly thought of as industry standard, but it does my students no good if they can't/won't read it. Campbell is a great reference manual, but it accentuates vocabulary a bit to much for my tastes and is written at a very high reading level and in a rather dense, dry academic style. My constituency is primarily from blue-collar, solid middle class families and they just found Campbell unapproachable. So I switched, and although Raven is not a panacea, I get more readers. It is a bit chattier style of writing and if I pick and choose my chapters carefully, we stay at a reasonable level of details. However, Raven is not without its flaws. My two major critiques:
  • The writing is uneven from chapter to chapter. Some of the authors have targeted their writing and their depth to the right level and some dove into jargon waaaaay too much (Chapter 18 Control of Gene Expression -- someone really loves their motifs!). The book needs a heavy-handed editor to even it out across the board.

  • I don't agree with the organization of a number of chapters. Who would start a discussion of macromolecules with proteins (Chapter 3)? Those are the hardest biomolecules to understand. Start with sugars and build from there, I say! pedagogical differences.

So the Holy Grail of the right textbook will remain out there. Just do the best with what you have.

Wednesday, September 05, 2007

AP stands for Auto-Pilot!

I have two large AP Biology classes this year. I'm excited to have built up the program at our school to this level but it will require me to change some of my teaching strategies in this course. In particular, I will have to manage essay grading differently (but more on that later).

I've decided this year that AP stands for Auto-Pilot. The Auto-Pilot regimen will be that students need to work more and more independently as the year progresses. My first AP initiative will be to start them cleaning up after themselves from Day One -- putting all labware, supplies, books, notebooks away neatly!

As a pleasant consequence of the AP audit (maybe the only one), I now have a day-to-day plan for the year. Although that was imagined in an ideal scenario, so we'll see if I can live up to it. But I hope this allows me to move to a more Auto-Pilot mode myself!


My "Intro" Powerpoint presentation can be found downloaded by clicking here. I emphasize how much work this class will be, what a student must to do to make it a success, and how much fun it will be. How can the science of life be boring, eh!?

Tuesday, September 04, 2007

A Survival Guide for Teaching Biology

It's the start of a new year of teaching AP Biology. My goal is to keep a teaching journal throughout the year to chronicle what's worked, what's not worked, my strategies, and my suggestions for next year.

So consider this a real-time teachers' guide — A Survival Guide for Teaching Biology.

I hope my musings help you!