Time to reflect on my students' most recent lab experience. This lab was designed by the chemistry teachers here at my high school and it explores the property known as density. The students recorded the mass and volumes of 1, 2, and 3 bars of a metal (aluminum, brass, zinc, or copper), compiled the class data, performed calculations on the data, and produced a graph of the compiled averages. They then wrote a conclusion using lab report guidelines provided by the teacher.
1. How should lab journals be structured?
Coming from a background in industry, I would like my students to strucure their lab notebooks in a professional way that reflects industry standards. This would include the following:
In this model the data collection is separate from the lab report, and I would expect the lab report to simulate the format of real world scientific papers, with introduction, methods and materials, results, discussion, and conclusion. This view differs drastically from what I have seen implemented in high school chemistry classrooms, which rarely distinguish between lab notebook and lab report. Indeed I have never seen a high school chemistry classroom where the students keep a separate "lab notebook."
I have two-fold reasoning for this format of lab notebooks and reports. First, being that it is consistent with what scientists in the field would be doing. Lab notebooks are, in fact, legal documents and proper notebook keeping is something many of the trainees at my company struggled with since it is not really taught in schools. Second, writing full lab reports are important not only to again simulate real-world scientists, but also to promote literacy through researching and reading as well as writing. Literacy is a huge issue and science is notorious for ignoring that aspect of education.
Back to the experiment...
2. Is this appropriate for the ability and understanding of the students?
Yes and no. The data collection portion of the lab was very appropriate and built on skills the students had been working on for the previous lab. The analysis is where things got sticky. The students encountered percent error calculations and graphing procedures that had not been introduced in the class. The lab was supposed to be the modality in which the students learned these topics, but rather than performing the task independently they had to copy the instructors model since they had not yet learned the procedures.
3. What type of research do students need to do to extend their understanding?
Students should research density, how it is used to determine characteristics of a material, whether it will sink or float, how it is used to identify unknowns, just general applications for the concept of density. They can measure density but to extend their understanding they need to wield this skill in context.
4. Is the curriculum unit appropriate for this group of 10-12th grade chemistry students?
This unit introduces students to scientific measurement and allows them a safe and simple space to practice these critical lab skills. It would be more appropriate if slightly more time was spent discussing proper measuring technique and allowing the students to explore potential sources of incorrect measurement.
5. Do students have the opportunity to devise their own experiments?
In this case, no. Students follow a very cut and dry step-by-step procedure. It doesn't appear that there will be many opportunity for the students to devise their own experiments due to the perceived pressure to cover the quantity of content required by the current standards.
6. Are all students participating equally?
In general I would say no. There are a handful of students that are very obviously detached from the activities and sit back while their lab group does the experiment for them. In the class there is an imbalance in discussion participation, with 3-4 students dominating the conversation and the other 30 remaining silent.
1. How should lab journals be structured?
Coming from a background in industry, I would like my students to strucure their lab notebooks in a professional way that reflects industry standards. This would include the following:
- Project Title (at the top of each page)
- Purpose/Hypothesis
- Methods Used
- Materials
- Procedure including all raw data measurements
- Results andCalculations
- Comments (result expected or unexpected?)
In this model the data collection is separate from the lab report, and I would expect the lab report to simulate the format of real world scientific papers, with introduction, methods and materials, results, discussion, and conclusion. This view differs drastically from what I have seen implemented in high school chemistry classrooms, which rarely distinguish between lab notebook and lab report. Indeed I have never seen a high school chemistry classroom where the students keep a separate "lab notebook."
I have two-fold reasoning for this format of lab notebooks and reports. First, being that it is consistent with what scientists in the field would be doing. Lab notebooks are, in fact, legal documents and proper notebook keeping is something many of the trainees at my company struggled with since it is not really taught in schools. Second, writing full lab reports are important not only to again simulate real-world scientists, but also to promote literacy through researching and reading as well as writing. Literacy is a huge issue and science is notorious for ignoring that aspect of education.
Back to the experiment...
2. Is this appropriate for the ability and understanding of the students?
Yes and no. The data collection portion of the lab was very appropriate and built on skills the students had been working on for the previous lab. The analysis is where things got sticky. The students encountered percent error calculations and graphing procedures that had not been introduced in the class. The lab was supposed to be the modality in which the students learned these topics, but rather than performing the task independently they had to copy the instructors model since they had not yet learned the procedures.
3. What type of research do students need to do to extend their understanding?
Students should research density, how it is used to determine characteristics of a material, whether it will sink or float, how it is used to identify unknowns, just general applications for the concept of density. They can measure density but to extend their understanding they need to wield this skill in context.
4. Is the curriculum unit appropriate for this group of 10-12th grade chemistry students?
This unit introduces students to scientific measurement and allows them a safe and simple space to practice these critical lab skills. It would be more appropriate if slightly more time was spent discussing proper measuring technique and allowing the students to explore potential sources of incorrect measurement.
5. Do students have the opportunity to devise their own experiments?
In this case, no. Students follow a very cut and dry step-by-step procedure. It doesn't appear that there will be many opportunity for the students to devise their own experiments due to the perceived pressure to cover the quantity of content required by the current standards.
6. Are all students participating equally?
In general I would say no. There are a handful of students that are very obviously detached from the activities and sit back while their lab group does the experiment for them. In the class there is an imbalance in discussion participation, with 3-4 students dominating the conversation and the other 30 remaining silent.