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Advanced Chemical Lab Design

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glassware on pink background, text: Advanced High School Course: Lab Design

Last spring I went to my administration with a proposal. I wanted to design an advanced laboratory course for a few students who had already taken AP Chemistry and wanted additional laboratory experience. With approval from the school administration and the Board, I began planning.

First, I considered the needs of my students. I had one student who needed help preparing for the lab portion of the competition. I had other students who wanted opportunities to apply the concepts they had learned in AP Chemistry. I also had a few students who had not taken AP, but were highly motivated and excited about a class like this. I wanted the class to challenge each of the students while allowing for individual growth. Most importantly, I wanted to provide authentic opportunities where my students could design experiments, troubleshoot protocols, peer review each other, and draw and defend their conclusions.

Second, I started defining and drafting the learning goals for the class I envisioned. I conducted a little research online and read through expected learning outcomes from a few different colleges and universities. The and were particularly helpful. I decided on four main objectives: Fundamentals and Applications of Theories, Experimental Design, Analysis, and Communication. I then wrote “I can” statements (I use Standards-Based Learning in all my classes - learn more from !) in student-friendly language. You can see the results below.

 

​​​​​​COURSE OBJECTIVES

Objective 1: Fundamentals and Applications of Theories

Students will have a firm foundation in the fundamentals and application of current chemical and scientific theories including those in Analytical, Inorganic, Organic and Physical Chemistries. Students will be skilled in problem solving, critical thinking and analytical reasoning as applied to scientific problems.

  • I can identify and apply the proper laboratory technique/theory required to reach the desired outcome of the laboratory goal.
  • I can apply appropriate mathematical reasoning and perform calculations within scientific theories.
  • I can apply known scientific principles to develop and support an evidence-based argument.

Objective 2: Experimental Design

Students will be able to design and carry out scientific experiments.

  • I can choose and construct the appropriate apparatus, technique, and procedures necessary to accomplish the laboratory goal.
  • I can apply technical and manipulative skills in using laboratory equipment, tools, materials, computer software
  • I can design experiments that are safe and produce minimal waste.
  • I can troubleshoot problems arising during laboratory investigations.
  • I can design experiments to minimize error and uncertainty in results.

Objective 3: Analysis

Students will accurately record and analyze the results of scientific experiments.

  • I can identify data and observations necessary to accomplish the laboratory goal.
  • I can identify and interpret a data set for relevant evidence.
  • I can identify and evaluate errors and uncertainty when analyzing and drawing conclusions from data.
  • I can maintain accurate records during a laboratory experiment.

Objective 4: Communication

Students will be able to clearly communicate the results of scientific work in oral, written and electronic formats to both scientists and the public at large.

  • I can present my findings clearly, concisely, and on time.
  • I can cite relevant scientific research to support my experimental plan and conclusions.

CHALLENGES

Finally, I selected different laboratory challenges for the students to work on. I began searching the archives of old and inquiry-based labs from and . Sometimes everyone worked on the same challenge. Other times they were given choices. There were times we worked in groups and times students worked individually. The students were afforded the freedom to make almost all the design decisions on their own or with each other.

After the experiments were completed, students had to decide how to communicate their findings with each other. I did not want them writing traditional lab reports. It is my opinion that traditional lab reports are outdated and no longer relevant to our students. Instead, I wanted them to learn how to write a journal article. Most of the students in this course will go on to publish during their graduate (and even undergraduate) studies. I provided the following resource, adapted from the American Chemical Society’s webpage to help them format their formal writing: . In addition to honing their writing skills, I wanted to give them experience discussing and defending their findings and conclusions. In order to achieve this, we also held poster sessions. The students created “posters” on whiteboards. They would print out graphs or images and sometimes write out their conclusions with markers. We would all gather around and read everyone’s boards. Then, students could ask questions or challenge each other to explain their conclusions. These sessions gave me goosebumps - the students were so invested in helping each other. They would offer alternative ideas, or try to help each other troubleshoot protocols if something wasn’t working. If one student encountered a challenge or recorded some strange data, we would come together and discuss possible sources of error. Sometimes the students would run the experiment again to try and replicate the data.

I have linked four challenges I adapted from the Olympiad laboratory portion below. I usually had two tiers of challenges for students to choose from. In some cases, I wanted the students who hadn’t taken AP Chemistry to have an option they could complete without having to do extensive research on a topic they hadn’t yet studied.

I asked students to complete four challenges before the final collaborative project. For the final project our class was tasked with solving a school problem. Our second floor boiler malfunctioned and stopped working. Our Assistant Head of School went to investigate and discovered a significant amount of sediment built up on the heating element. He collected a sample and gave it to our class to analyze. The students researched qualitative analysis and water quality reports to design the protocol. They were able to identify the composition of the sediment and prepare a detailed report for the Assistant Head.

Students were assessed using the rubric found in figure 1 below (you can download the rubric from the Supporting Information). I also asked them to reflect on their own progress.

Figure 1: Rubric for Student Challenges.

 

Here are some samples of student reflections after they completed the course:

“I learned a tremendous amount about lab equipment and the function of each piece over the course of this class. I am much more familiar now with using the various stands, scales, and glass containers. I also developed my skills in accurately measuring out volumes of solutions, something that we did in almost every lab. Over the course of this class, I also feel that I improved my understanding of the various theories and concepts associated with these labs, which ultimately helped me make important observations. My ability to notice potential sources of error also improved as I began to take note of important error-producing steps in the procedures.”

 

“After taking this class, I feel more comfortable working without a substantial amount of guidance. I have learned how to take into consideration potential ways that the experiment would fail and construct a procedure that would produce the most accurate results. I also learned about the importance of recording every step of a procedure so that when the results are not accurate or are not achieved, I can go back through each step and evaluate whether or not they are correct. I also learned how to properly dispose of certain substances.”

 

“I feel that my ability to pay attention to an experiment and take note of important occurrences has improved tremendously. I can identify potential sources of error before the experiment begins and I can also identify ways to ensure consistent data collection. Taking this class has also taught me the importance of organizing data. There were some instances where trials had to be redone due to unorganized data, which further compounded with the fact that there was less time for the trials, all resulting in poor data. This was especially noticed during analysis as inconsistent trends sometimes produced nonsensical/inaccurate conclusions.”

 

“The use of the white boards in this class helped me tremendously with organizing my data and other information for presentation. It also gave me another way to think about piecing the puzzle together other than the obvious format of a typed lab report. I also practiced sharing ideas with classmates in order to figure out an appropriate procedure. In doing so, I also had to consider other points of view that were sometimes contrary to my own - something I will need to be able to do if I decide to pursue science in further education and/or my future career.”

 

“I believe classes like this are highly beneficial to students in general. It is different from the typical classroom setting and brings new challenges that a student will need to adapt to, much like the real world. For myself, I had to get used to figuring out the problems and working more independently than before. Having to create a procedure by myself was a definite change of pace and it forced me to think and communicate more. For future scientists, these skills are essential and though they will be taught later on, it is ideal to get started earlier.”

Supporting Information: 
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