Writing a Lab Report: (The Scientific Method in Action part 3)
Lesson 8 of 9
Objective: Students analyze data collected during an experiment and determine whether their hypothesis was true or false.
In this lesson, students will organize and analyze the data they recorded during the previous lesson. Using this data, they will look for evidence that supports or refutes the initial hypothesis they postulated during the design of the experiment. Finally, they will organize their data and conclusions in a lab report and answer reflective questions.
This lesson targets three standards.
First, a writing standard is covered in that the lesson requires students to write an informative or explanatory text, specifically explaining the procedures they followed in the experiment and how those procedures were intended to collect data, and how that data would be used to prove or disprove a hypothesis.
Additionally, the writing must be clear and communicate scientific information clearly. This is not a creative writing project so students need to make certain that their writing is focused and maintains a somewhat formal tone.
Finally, this standard is targeted by the conclusion and reflection sections of the lab report as students are required to make a definitive statement about whether or not their initial hypothesis was correct as well as answer more reflective questions about how they might improve their experiment, providing evidence from their experiment as their justification.
At the beginning of the class, I ask students to arrange themselves in their lab groups and take out all the materials from the previous day’s experiment (this would include data tables, written tasks, the original experimental design, video footage, and any additional written observations). If you collected these resources from the students following the experiment, then you may want to ask for a volunteer to help you distribute the relevant materials to the lab groups.
After groups are settled and have their materials, I ask if they had fun yesterday. Since spinning around and falling down are both fun and funny, most students enthusiastically respond in the affirmative. I then ask students if we just went outside to have fun (of course not… this is science!), and ask why we conducted the experiment. I ask for student volunteers to remind us that we were investigating physiologic vertigo and how it affected someone’s ability to perform basic tasks (for a full description of the rationale for the experiment, see the introduction section of part 1 of this lesson sequence).
I then remind students that conducting an experiment is only half-way through the steps of the scientific method and ask what else remains. Hopefully students can generate that we need to “form conclusions” and “publish results”. I then ask how will we form conclusions, to which students should respond “by making sense of data”. I tell them that they will “publish results” in the form of a lab report.
Once the groans die down, I distribute the resources and we begin writing the lab report.
Writing the Lab Report
To begin actually writing the lab report, I distribute one group lab report for each group and one individual lab report for each student. I then explain to students that they are each individually responsible for completing an individual lab report, and that the group as a whole must then come together to complete the group lab report.
The rationale for having two separate lab reports is,
- It’s a great way to divide the labor equitably and make sure that no one student does all the work while the other students goof off (if an individual chooses not to work on their individual lab report, it won’t affect the other members’ grades).
- It requires each and every student to practice the writing skills in the targeted standards.
- It requires both self reliance (completing your individual section) and cooperation (coming together to complete the group lab report).
Both the individual and group lab report worksheets provide scaffolds for organizing information. For the individual lab reports, each student is tasked with defining vertigo and equilibrium, stating their group’s initial hypothesis, and then describing one of the tasks their group performed during the experiment. This description of a single task should include a detailed explanation of the procedure they followed, the data they collected, how that data proved or disproved their hypothesis, and how they might alter the specific task if they were to conduct the experiment again.
Once students have all the necessary materials, I tell the group to split up their data and give the relevant data table to the student that will be writing about that task. If students were thorough in their completion of the data tables during the experiment, they should already have most of the information necessary to transfer the procedural explanations and collected data directly to the relevant sections of the lab report.
As students are working on the individual lab reports, I move from group to group checking in to see if there are questions or issues (it’s also necessary to keep eyes and ears open for groups on the opposite side of class that may have hands raised for a question). When I stop by an individual group, I usually check their procedural explanations, making sure they’re as detailed as possible and that they “put it all on the page” and don’t assume the reader knows what they’re talking about. I remind them that a scientific report should have enough detail that another scientist could conduct the experiment exactly as they did. As far as data, I make sure they’re providing both quantitative and qualitative data. If they reply that they only collected one kind or another, or if the data they did collect seems limited or irrelevant, I point that out and suggest they consider addressing that fact when they answer the reflective question about what they would do differently if they repeated the experiment.
One thing that is especially useful during this time is if students recorded video of their experiment. In the cases where the written data is sparse, it should be easy to point out examples where students can collect additional data from watching the video (e.g., if they didn’t time some aspect of the task, they can use a stopwatch while during playback of the video to collect that quantitative data).
After about 15-20 minutes, I tell students that they should be moving on to the group lab report. For the group report, students should each have their individual lab report section to consult. The group lab report asks students to restate their group’s initial hypothesis and explain the reasoning behind their hypothesis. They then must identify the variables and groups of the experiment and provide short descriptions of the tasks they conducted.
The final part of the group lab report requires them to state a conclusion about their hypothesis and support it with data collected during the experiment. I require students to write this conclusion as a multi-paragraph document on a separate paper and encourage them to use a basic 5 paragraph format with an introduction, support, and conclusion. Students may struggle with this section, but I try and point them back to the data if they get stuck. It’s sometimes necessary to remind them that it’s ok if the results of their experiment were inconclusive and, in that case, encourage them to explain why they can not make a clear conclusion, citing seemingly conflicting data as necessary.
Following that conclusion, groups must answer a question about a follow-up experiment they could conduct to further study vertigo. These questions may relate to duration (e.g., How long does the feeling of vertigo impair ability?), intensity (e.g., Does more/faster spinning produce more significant impairment), acclimation (e.g., Can your body “learn” to deal with vertigo and gradually get better at performing tasks?), or any other question that might have occurred to them during the experiment.
There is also an extra credit question about how spinning causes vertigo. For groups that finish quicker than others, I encourage them to research the question. A good explanation is provided here.
When there is about 5 minutes left in class, I tell students how I would like them to arrange the lab report and staple it together:
1. Group lab report (with all group members’ names)
2. Individual lab reports (with the individual student’s name)
3. Appendix: data tables, experimental design, written tasks, any additional data
(I have this written on the board earlier, but direct their attention to it as we wrap up the class)
If they want to do the extra credit but have run out of time, I let them know that they can complete it on a separate sheet of paper and turn it in next time. I’ll ask for explanations of the extra credit and explain the answer at the beginning of the next class meeting.
Additionally, I let groups know that if they need additional time, they can complete their lab report after school or for homework.