Labor Or Oratory

It's Wednesday morning and Delilah enters the classroom and asks "Are we doing a lab today, Mr. H?" I answer in the affirmative and she responds with an enthusiastic "Yes." Her question and response elicit a wealth of emotion inside of me as I continue preparations for the lab. Most of these emotions are negative. I am upset, disappointed, and feeling a sense of defeat.

You might be asking "How could a physics teacher be upset about a student's expression of enthusiasm for a lab?" The answer is easy. We are four months into the school year and by now I know that Delilah isn't excited about doing a lab. Rather, she is excited about being in the lab. She is excited about being in the lab where she can talk and not being in her seat where she must be still, attentive and quiet. She is not excited about pondering a question, devising a procedure, collecting data, analyzing data and completing a report. When it comes to doing those tasks, Delilah will definitely disappear into the background. And unfortunately, her presence in the lab group will likely draw one or two more members of the group into the background for off-task conversation and socialization. Delilah talks with a friend, allowing her partners to do most the work;  she joins them near the end of the lab to get their data and endures their efforts to analyze it.

Delilah's attitude towards lab is like a contagious infection that spreads to those with whom she has social contact with. This is the infection which can destroy a laboratory environment, transforming it from an environment of scientific inquiry into one of social inquiry. It is not the labor of the Laboratory that has Delilah excited on this Wednesday morning. It is the oratory of the Laboratory which has Delilah excited. And that explains in part why the negative emotions flush through my body on this Wednesday morning.

During the first days of the course, I make an effort to create the proper mindset towards the laboratory.   With as much drama as I can muster, I explain to students that ...

The laboratory is sacred. It is the place in the room in the room where you become engaged in the doing of science. The answers to scientific questions are found in the back of the room - in the laboratory. It is in the laboratory that you will be engaged in the most important activities in science - asking and answering a question through observation, measurement and data analysis.

Physics is not a spectator sport. You must be mentally active. Those who approach physics in passive mode will be less thrilled and most disappointed by the course. Physics involves involvement! It demands a proactive approach to learning. It demands pondering, thinking, problem-solving, inquiring. To be successful, you will have to both sort it all out ;and put it together. And the location in the room where you will be most on your own and most active will be in the laboratory. You won't be alone in the lab, but you will be on your own - on your own to ponder a question, to adopt an approach to answer it, to collect some data and to sort out the meaning of what the data says about the answer to the question. In this course, you will be quite active in the lab, involved in a question, pondering and thinking through the results, and determining the answer to the question. This is science and science happens in the lab.

I repeat the message throughout the first weeks of the course with the fervor of an evangelist. I tell stories, design experiences and emphasize the central role of lab in the course. And now four months into the course, it is evident that my view of the laboratory and Delilah's view of the laboratory clash. I view it as the Laboratory and she views it as the labOratory. It is the same place in the room, but the emphasis, the motives, the reason for going there and the type of pleasure which is derived from there are polar opposites. My laboratory is sacred sermon has not been received. In fact, it has been sacrilegiously trampled upon. The place in the room which I spent several weeks consecrating to the service of science has been profaned.  For Delilah, lab time has in effect become recess time. It is not a time in which she becomes engaged in the most important aspect of the course - doing science; rather it is a time in which she assumes she can exercise her right to avoid science.

The truth is that my message regarding the nature of the laboratory has not yet been received by all. There are more Delilahs out there - in my class room and probably in yours. Should we be surprised that a large percentage of our students do not share our passion towards the laboratory? It is the proverbial dilemma: you can lead a horse to water, but you can't make it drink.

But is this the end of the story?  Should we just throw in the towel, give up and let the Delilahs be Delilah? No!  Come back in a couple of weeks for ... the rest of the story.



This week's article is contributed by Tom Henderson. Tom is the author of The Physics Classroom website.  He is a graduate of the University of Illinois in Champaign-Urbana, Illinois. He has been a high school physics teacher since 1989. Tom currently teaches Honors ChemPhys (Physics portion) and Honors Chemistry at Glenbrook South High School in Glenview, IL, where he has taught since 1989. 

Improving Students' Scientific Literacy - ACT Season

It's ACT season again. Juniors (and in some instances, sophomores, freshman, etc.) across the country will be marching into test rooms to take a battery of tests, the outcome of which could effect their ability to get into the college of their choice. For many high school juniors, taking the ACT is an optional experience. For juniors in Illinois where I teach (and in other states), taking the ACT is not optional. It is part of the state-mandated testing program used to assess student achievement and the job which schools are doing to promote student achievement.

It may seem to a physics teacher that a 40-question science test has little to do with our teaching of science. But it does! The ACT publishes a collection of College Readiness Standards (CRS) for Science - standards upon which questions are based. The CRS (or curses, as a colleague of mine refers to them) are broken into three strands. The three strands of standards are:

• Interpretation of Data
• Scientific Investigation
• Evaluation of Models, Inferences and Experimental Results

As a physics teacher, those three strands have a lot to do with my teaching of physics. And most particularly, they have a lot to do with the implementation of my physics lab program.

If you give the College Readiness Standards a closer look, you will notice that they are great standards for your lab program. For instance, consider the following standards from the Interpretation of Data strand:

• Determine how the value of one variable changes as the value of another variable changes ... .
• Translate information into a table, graph or diagram.
• Identify and/or use a simple (e.g., linear) mathematical relationship between data.
• Identify and/or use a complex (e.g., nonlinear) mathematical relationship between data.
• Extrapolate from data points in a table or graph.

I would love my students to become more skilled at these types of activities as a result of participation in my lab program. By providing students with practice at developing these skills through lab activities and post-lab analysis sessions, I am nurturing better science students, but also preparing students for success on the ACT test.

Now let's take a look at some College Readiness Standards under the Scientific Investigation strand:

• Understand a simple experimental design.
• Understand a complex experimental design.
• Predict the results of an additional trial or measurement in an experiment.
• Identify an alternate method for testing a hypothesis.
• Predict how modifying the design or methods of an experiment will affect results.

Once more, these are great standards for a lab program. If my students could develop their understanding and skills in the areas of these standards, they would be much better lab students. And they would also perform better on the ACT test.

Finally, lets look at a few College Readiness Standards under the Evaluation of Models, Inferences and Experimental Results strand:

• Select a simple hypothesis, prediction or conclusion that is supported by a data presentation or a model.
• Determine whether given information supports or contradicts a hypothesis or conclusion, and why.
• Identify strengths or weaknesses in one or more models.
• Determine which model(s) is(are) strengthened or weakened by new information.
• Use new information to make a prediction based on a model.

We likely all agree that students need to improve their skills of thinking critically, analyzing information, designing experimental procedures, interpreting data, evaluating models in light of evidence, and drawing evidence-based conclusions. If my physics lab program (and other parts of my physics curriculum) were instrumental in improving these skills, then I would consider the lab program and supporting curriculum to be a success.

With confidence, I can say it's ACT season. Every day of the year, it should be ACT season in my physics classroom. Every day of the year, students should be improving their scientific literacy skills. It's ACT season again always.




This month's article is contributed by Tom Henderson. Tom is the author of The Physics Classroom website.  He is a graduate of the University of Illinois in Champaign-Urbana, Illinois. He has been a high school physics teacher since 1989. Tom currently teaches Honors ChemPhys (Physics portion) and Honors Chemistry at Glenbrook South High School in Glenview, IL, where he has taught since 1989.

Tom invites those teachers who are interested in providing physics students with practice at taking ACT test type items to view and even use the following documents as practice opportunities within the classroom:

• Research Summaries Passage: Head Injuries and Football
• Data Representation Passage: Ball-Bat Collisions

The End of Semester Project

Ideas for an end-of-semester project

Our second quarter schedule in the Regular Physics course at Glenbrook South includes two weeks after winter break, plus an additional week in January for final exams. For the second year in a row, my colleagues and I have used the last two weeks of the quarter in January for an extensive, lab-based student project with our Physics 163 (middle-level) students. Students are given an open-ended challenge. They must design and run one or more lab investigations that link to several topics we have learned throughout the semester. Students are expected to select complex, measureable lab goals and use a variety of lab equipment in their investigations. Specific directions and the student rubric can be found here. The “pros” of this project are numerous: student interest is peaked by the opportunities for student choice, students connect topics they have learned throughout the quarter, students do thoughtful analysis, students get a taste of what real scientists do, students feel genuine pride at accomplishing a challenging task, and so on. Potential cons include the amount of class time that must be dedicated to the project, the need for laboratory equipment, and the handful of projects that inevitably don’t meet the teacher’s high expectations. I will discuss implementation of the project, state the pros and cons of the project, share a few case studies, and discuss ideas for improving the project and minimizing some of the cons.

Timeline for the project

Prior to introduction: The teachers selected a list of equipment they would provide for students. We then set up the back of the classroom like a “buffet” of equipment. Students would be expected to borrow equipment during the class periods and then return everything to clearly labeled bins in the back. The exceptions were high-theft-risk items such as cameras and electronic balances; students checked these out from the teacher when needed. Teachers also reflected on their desires for the lab and updated the directions (found here) as necessary. The project was scheduled for the last two weeks of second semester. Students had already studied motion in 1-D, forces, 2-D motion and forces, projectiles, momentum, and energy. It was key to do this project at the end of the semester so that students had a range of physics knowledge from which to draw.

The introduction: The project was scheduled for seven class days over a two-week period. On the first day of the project, I handed out the directions and rubric and explained the overall goal. Students were told not to worry if their initial reaction was to feel stumped. Students were encouraged to look back over their lab journal and think about the labs we had done throughout the semester. I also suggested that kids should look at the equipment provided in the back of the classroom. I told students that this was not the only equipment they could use and that they were welcome to ask for additional equipment as needed. On this day and several times throughout the project, students asked for an exact number of labs or topics required. In the past, I told them a minimum number of labs required. This year, I was careful to not give a numerical answer to that question. Rather, I reminded students that their goal was to create a lab (or labs) that is complex, not a repeat of something we’ve already done, and that spans several physics topics. I reinforced that they could do this in one very large and complex lab or with several smaller labs. Students were told that they could pick a partner but that they’d each need to record data and produce their own lab write-up (goal, procedure, data, calculations, and conclusion).

The first few days: The first few days involved a lot of student brainstorming as they tried to pick appropriate goals. When students were stumped, I asked them if they had interests outside of class that they wanted to link to physics. For example, one group was interested in modeling how an airplane takes off from an aircraft carrier. Their project used motion and force sensors to determine the effect of air resistance on a small vehicle. They also linked their goal to work and kinematics. Another group was interested in golf balls. They did a video analysis of their golf swing and also made distance measurements; they then used their data to link work and energy to projectiles and air resistance. I found that I did a lot of listening and suggesting at the beginning of the project. I tried not to squash an excited student’s idea even if it initially seemed too simple. Rather, I encouraged the student to start on that lab and then think about what additional topics they could work into the lab as they did it; I also offered ideas about how they could bring in additional physics topics to their project.

The middle: The middle of the project involved lots of discussions about experimental methods. Frequently, I ran to the prep room behind my classroom to get additional materials. A student modeling collisions with an air bag in a car wanted Ziploc bags; a student connecting energy to projectiles and work done by friction wanted hot wheels tracks and cars; a student launching a projectile into a cup to study projectiles, collisions, and energy wanted cups; students studying friction wanted a variety surfaces made of different materials; students projecting marbles into cars wanted cotton balls. The list goes on. I was lucky to have lots of materials on hand; at the same time, teachers at schools with a smaller variety of materials could simply have students bring in any additional items they wanted to use. I was surprised by how many students chose to use video cameras and analyze the video using the LoggerPro Vernier software. We didn’t use the cameras to do video analysis more than about once a month during the semester. However, students were very comfortable with the cameras. Video footage (or should I say “bitage”—no need to measure feet of tape any more) is a huge part of students’ world and they bring a lot of technical expertise to the table. A large percentage of students also used Vernier probeware such as motion sensors or force probes during their project.

The results: As I am writing this article, I am at the front of the classroom and my students are taking their final exam. In an hour, when the exam ends, they will turn in their journals which include their final project. A few turned in their projects already and I have graded those. The results of student learning will vary from student-to-student. Some students will have learned more about analyzing videos while others may have learned more about analyzing errors in the lab. However, I feel that all students benefited from experiencing what “real science” looks like. The students were invested and excited about their project and did think deeply about the connections between the physics topics. The process itself was valuable. Admittedly, the students did not all learn the same physics content during the project. There is a constant pull between wanting to give the students time to investigate and making sure to cover enough topics. In December, I was wondering if I really wanted to do this project again. I was thinking about how we could spend the two weeks doing another chapter in the book instead. I am so glad I did the project again and remembered how much I value it. Several case studies below show examples of student experimentation. The case studies also illustrate how varied the projects can be. Teachers should be flexible and reasonably comfortable with physics and experimentation so that they can guide their students.

Case Studies

Case study #1:

The image to the right shows a stuffed pig swinging like a pendulum from a rope attached to the classroom ceiling. Why? Because this group was (a) obsessed with the stuffed pig, and (b) attemping to have the pig safely land on the foam on the floor. A razor cut the string when the pig was in the lowest position of its arc. They did a vector analysis of the tension, used energy to predict the velocity at the bottom, and then used projectile equations to determine where the foam should be placed. This was only part of their analysis. Another group did something similar, but they had the pendulum hit a stationary object that then became a projectile. This meant that they were also doing a momentum collision analysis along with energy and projectiles.

Case study #2:

The group with the two photos here set up a projectile launcher at an angle. They found the initial velocity of the launcher and determined where to set a tube (incined plane) to catch the marble. At the bottom of the tube, there was a cart with a cup on it as shown in the picture on the right. They did a work-energy analysis as the marble slowed to a stop in the cart.

Case study #3:

The girl in the movie still-shot at the right is an avid horse-rider. Her goal was to learn about the power involved in a horse’s jump and also to analyze the motion of the horse in the air and see how much of an effect air resistance had on the horse’s motion. She relied on the video-analysis feature of the Vernier software program Logger Pro. As this image shows, I allowed students to check out cameras if they wanted to do a real-world experiment that couldn’t be modeled in the classroom. Students checked out cameras to help them analyze golfing, sledding, driving, and the like.

Ideas for extending the project:

In reflecting on the past two weeks, I feel that there were two big things missing from this project. I would have liked the students to have received written (as opposed to only oral) feedback from me during the project. I would have also liked students to share their projects with the rest of the class. Both of these were accomplished by a co-worker of mine. He had the students present their projects not in a journal but on their class Wiki. Students could see each others’ projects, and my co-worker commented (in red text, of course) on their writing as the project went on.


This month's article is contributed by Debbie Berlin. Debbie is a graduate of Northwestern University in Evanston, Illinois. She has been a high school physics teacher for 11 years. Debbie currently teaches Regular Physics and Honors Physics at Glenbrook South High School in Glenview, IL, where she has taught since 2004.