Foundations: Shifting Lab Reports in AP® Physics

I have written about my overall approach to labs in both Physics and AP® Physics in a previous post.  Everything in that post still applies in my courses today, including the two lab skills I use for lab report assessment.  However, I am shifting how I support students in their writing of formal lab reports, which I only include in my AP Physics course.  Over the years, despite any preparation we do as a class and any resources I provide to ensure universal understanding of the goals of a lab report and the expectations of the content and analysis, my students struggle with the first few reports of each academic year, learning what is expected seemingly through trial and error.  This summer, I worked to add more scaffolding and support to my lab report templates to (hopefully!) help my students experience the value of documentation.  I am going to share the details of this new approach here and then I will make sure to add an update when I see how the students take to this new system!

What was I doing before?

This isn't the first time I have used a template in which I break out the sections of a lab report to give students a starting point and avoid the intimidation factor of the blank, white page!  I shared a pdf of my template in my previous post as well.  Here is what my templates used to look like:

You can see in the image above that there is a link for the students to reference.  This took the students through each section of the report and detailed the expectations.  I gave this same information to the students for every single lab report.  This made my life easier for sure and gave the students a familiar starting point each time they sat down to write.  However, I overestimated my students' capacity to shift their work depending on the context of the lab.  I have realized this is a skill I need to help them practice!  This leads me to my plan for this year. Read on!

What do my NEW templates look like?

First, I decided to create a customized template for each lab investigation so I could include targeted questions and recommendations.  Second, I gradually reduced the level of my support in each subsequent template.  This means that my template for the first lab report of the year includes A LOT (TONS) of support and specificity about the expectations of each section.  The next template includes a bit less, allowing the students to build on their learning from their previous writing experience.  This incremental reduction of my support continues throughout the year.  To illustrate this with an example, below is the analysis section from my first lab report template of the year:

THE LINEARIZED GRAPH (FIRST LINEARIZATION OF THE YEAR!!! YES!!!!!!) You are going to analyze a LINEAR graph to determine the experimental launch velocity of the projectile. Basically, you can’t simply plot range vs launch angle because that relationship is NOT linear (look at the theoretical equation...not linear!).  So how do you know what to graph?  Let’s pretend that the theoretical relationship between range and launch angle is x = voϑ2.  Ignoring the fact that the units make NO SENSE here, you would plot x on the vertical axis and ϑ2 on the horizontal axis.  Then vo would be the slope of the best-fit line.  Look at the theoretical equation in section 1.  Think about what you would need to plot on the vertical and horizontal axes in order to get a linear relationship.  Once you decide that, make a table of the values you are going to plot and include it in this section with a brief explanation.  Remember, units in the title of the table only. Include an image of the graph of this manipulated data from LoggerPro (make sure LoggerPro is in degree mode by going to File → Settings and selecting Degrees).  Your plot must have a clear best-fit line superimposed with the equation visible. The axes must be labeled (including units if needed).   Explain and digest the meaning of the graph.  Describe what the graph is showing, state the best-fit equation (include units on numerical values only when you write out the equation and use proper variables based on the axes of the graph, example not based on this lab: x = 7.5m/s*t + 0.1m), discuss the meaning of the slope and y-intercept and whether they make sense, state and discuss the correlation value, and extract and discuss the launch velocity.  Basically, discuss your graph and results in detail.  Don’t forget units on all numerical values!  If you do any math, show your steps and explain. Note: you can’t determine percent error or percent difference because you don’t know the actual launch velocity.  In future labs, we will be able to compare to a known value.  This time, we are looking at the trend in our data to see how well it fits the theoretical model we are applying.

This is where your work goes for section 3!! Delete this message, please :)

THE NONLINEAR GRAPH You are going to analyze a second graph (not linear) to predict the angle of launch that would maximize the range.   Include a plot of the data with an APPROPRIATE best-fit curve applied.    Again, make sure the image of the graph is clear and labeled.  Explain and digest the graph once again as for the previous graph.  Don’t forget to state/discuss the shape and values of the best-fit curve terms, discuss the correlation value, and comment on anything else that stands out to you as accurate or inaccurate when you compare to the theoretical equation from section 1. Use the best-fit curve equation to calculate the experimental angle at which max range would occur. Ensure any math you do to determine the experimental angle is documented, step-by-step.  Remember to put units on all numerical values. Now you need to see if the angle you calculated makes sense.  Describe what the theoretical angle would be and how you know it.  Determine the percent error between the angle you found from the graph (experimental) and the theoretical angle and discuss your results. (% error = abs(experimental value - theoretical value)/theoretical value x 100%)  Show all your work and include units on all numerical values!

This is where your work goes for section 4!! Delete this message, please :)

There is SO MUCH detail here!  The students are linearizing on their own for the first time using software they have used very little.  By comparison, below is the analysis section from my last lab report template of the year:

LINEARIZATION!! Create a data table of the manipulated data you calculated for your first linearized graph.  This should be of the horizontal axis data and the vertical axis data (two columns only).  Include an explanation of why you decided to perform these calculations. Include a LINEAR graph of the data.  The graph must be created in LoggerPro with proper labels on the axes, including units. Your plot must have a clear best-fit line superimposed with the equation visible. Explain and digest the meaning of the graph.  Describe what the graph is showing, state the best-fit equation (include units on numerical values only when you write out the equation and use proper variables based on the axes of the graph, example not based on this lab: x = 7.5m/s*t + 0.1m), discuss the meaning of the slope and y-intercept and whether they make sense, and state and discuss the correlation value.  Basically, discuss your graph and results in detail.  Don’t forget units on all numerical values!  If you do any math, show your steps and explain. If you can perform % error, go ahead!

This is where your work goes for section 3!! Delete this message, please :)

You can see some repetition, and I have included a lot less guidance.  Ideally, students are now owning the report!  If you would like to see the complete templates for my first lab report and last lab report, feel free to do so by clicking on the links!  You will also see my introductory letter to my students on the first report file in which I introduce the process.  Please forgive any typos!  I am sure I will catch them as I use them this year!

I will update this post when I see these templates in action!!