Get Your Hands Dirty

A couple of years ago the AP Biology curriculum was significantly revised. For those of you who read this blog on a regular basis, this is not news to you. The revisions were a fantastic leap forward in the effort to prepare students for careers in science. We moved from students memorizing endless lists of enzymes and performing cookbook experiments with predetermined outcomes to deep data analysis and independently designed investigations. As difficult as the transition has been, I trust and believe that a better breed of science student is being built. These students are students who might actually be able to function as scientists once they hit the real world.

Likely my favorite component of the new curriculum is the student investigations. Previously students had been given complete sets of instructions to follow and the outcomes were already known. Students were simply working to demonstrate good lab technique in an effort to confirm previously discovered knowledge. Under the new format students are asked to investigate their own original questions through independently designed experiments. As a teacher I get so much joy watching the struggle that students go through in trying to develop good hypotheses and experiments that will actually serve as valid tests of those hypotheses. The students ... I'm not sure that they feel the same sense of joy, but they do learn a lot about the true nature of science. Perseverance eventually takes ceter stage and with time we finally rid them of the idea that their experiment FAILED. There are no failed experiments, just experiments that provided data that was contrary to that which one expected. It's a process that I love and a process that both of this week's weekly reporters mention in their account of the week that has been.

This weeks edition of the week in review is brought to you by Yesenia Leon and Sofia Ocegueda.

Yesenia Begins:

This week we have discussed several topics and proceeded to do some experiments. One of them was the osmosis and diffusion lab in which we saw how osmosis and diffusion was affected by the solution and molarity. The one that I found to be most appealing was procedure number 1 of this lab. In this experiment we got to cut three blocks of gelatin and use them as our cell models. They were all different sizes. We did this so we can figure out how a solution diffuses, if it diffuses faster at a lower surface area or at a higher surface area. We put them in containers and poured HCl (in this case vinegar) but before we did that we cut into the gelatin so the process could be quicker. We hypothesized that if you put HCl into each block, the smallest block would allow that solution to diffuse at a faster rate. Once we completed our procedure and did some calculations using the formula {Surface Area x Height=Volume} we came to the conclusion that our hypothesis was correct. The solution diffused at a faster rate in a smaller block. Also it was interesting to see how our result changed and were very noticeable when we left the gelatin stay overnight. In this lab we didn’t just follow steps at times we came up with our own steps and we were able to choose what and how we could handle our experiment (with a little bit of help). Finally, this lab was very useful since it helped us grasp the concept better and personally it helped me get this answer right on the test.

Sofia Concludes:

This week in AP Biology was…difficult. BUT I bet that’s old news to anyone who has had this class before. To start off this week, we had a test. A test on a Monday? Yes, on a Monday. Mr. Kite tested our knowledge on cells, and after I took that test, I realized I maybe didn’t know EVERYTHING on cells. Dreams=ruined. However, I did learn from my mistakes on the test. Tuesday was the start of a new unit- ENERGY! It was also the day of seeing my test grade. My eyes widened as Mr. Kite said that statement he eventually says once a year: “You didn’t do as good as the last test.” (NOOOO!) Wednesday we changed roles with Mr. Kite and taught each other the basic concepts of energy, using objectives. Through a series of drawings and unique contributions, we accomplished our goal. Thursday consisted of an online lab that helped us understand the function and concepts of enzymes. Through the module we were able to observe how enzymes could change shape, and what exactly had an effect on that. Friday was pre-lab day. Mr. Kite introduced a lab that dealt with enzymes and how to find their optimal environment. Our guinea pig for this experiment? Beef Liver! I can already hear the groans. But at least it’ll help us visualize the idea better. Still surviving AP Biology one day at a time.