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When I first started teaching high school chemistry, I did not want to do laboratory activities. I was intimidated by the amount of work needed to find, prepare, conduct, and grade labs that met curricular requirements. It was tedious and definitely not fun, and I hated it. It felt like every time I finally found or wrote an interesting lab activity that met the curriculum needs of my students, my students just did not want to do the lab. It became torture to them, and therefore torture to me as well.

What’s more, there was grading their lab reports. Earlier in my career, I had the students write only one or two lab reports per quarter. Even so, I could not seem to convey to the students why writing was an important skill (perhaps I was too green at the time), and most of them would not turn in their reports. When they did turn in their labs, they were often poorly written and took me several days to grade. It made me wish I had chosen a different subject to teach!

Solving the initial problem with cool labs

But suddenly, it hit me: what if I did labs that were simultaneously safe but also really cool to do? After all, on the rare occasion when I did do that, my students loved how the lab was hands-on, demonstrating very well the concepts they were learning that week. They also liked how it broke up the tedium of some aspects of the curriculum, and how it allowed them to take on diverse roles, differentiating their day and their activities. But, most of all, each lab was turned into a real-world scenario, which provided the labs with a sense of authenticity that other activities did not always have.

For example, to teach about polymerization as well as the scientific iteration process, I recently had my students engage in a lab from the perspective of a toy manufacturer who was trying to create a better bouncy ball. To do this lab, they had to research and write their own procedures for creating effective bouncy balls (measured by how high they bounced over a series of five trials), and then use the data from the first trial series to determine a new formulation for a second series. There was a lot of laughing and giggling in class, and the students eagerly engaged in the activity.

Solving the secondary problem with lab packets

At the end of the polymerization lab, I still needed to see my students’ thinking. Rather than have them show me this via a lab report, I had them do it with a lab packet. They answered questions in their lab packet from their data, a process that was similar to one they will follow in their future science fair projects. They also learned about a real-world scenario in which chemistry is used and, last but not least, they now all know what a polymer is!

I started this process with the lab packets quite a few years ago. It came about when I realized that when I was in college, I had written only two lab reports, and while I was in graduate school, had written only research papers and experimental papers. Proper lab reports, themselves, were a rarity. Initially, with the help of a colleague, I began to have students engage in writing scientific abstracts of their labs, as well as completing fairly exhaustive lab packets — much like the ones that they would create if they were to go to a four-year college. Since then, I have changed over to having my students (mostly) compose thoroughly-completed lab packets instead.

Where to begin

Now, I love using labs in my teaching! In changing my process, I was guided by my own two rules, especially after I took a course on Green Chemistry for high school teachers taught by Beyond Benign, a green chemistry education company based in Wilmington, MA.

• Rule 1: Any experiment I do with students has to be one I would have thought was fun or neat when I was a kid. I think that it is difficult to get excited about something that your own inner child would not.
• Rule 2: My experiments must be environmentally safe. For example, I did the famous copper (II) sulphate with steel wool lab activity recently with my students. For their safety, I premixed the compound into a solution for them (diluted to 0.5 g/L), thereby reducing the molarity of the solution and thus its toxicity as well. For disposal, rather than letting the students engage in the full clean-up process themselves, as would be my norm, I had them return their spent solutions to me. I did this because the classic reaction does not actually go to completion with the amount of copper (II) sulphate in the solution. So, I disposed of that waste product only after completing the reaction of the original solution, as well as several rounds of filtration with the products. Copper (II) sulphate, if not fully reacted, can enter the local water supply either by being tossed down a drain (if in a solution) or through rain exposure at local dumps that drain into a local water table and harm fish.¹ 

  In addition, I’ve standardized my lab assignments so that each packet contains five sections, which I describe below. I did this in part because it made it easier for me to assess the labs. Moreover, it seemed to match what I used to see in college lab manuals back when I was a T.A. and adjunct professor. My students seemed to respond well to the more consistent structure. It also made it much easier for me to write rubrics for the labs that only require subtle tweaking between each lab activity, versus creating a brand new and time-exhaustive rubric for each one.

Lab introduction

The first page of every lab activity handout in my classroom is structured the same way: it has the background and purpose section, which explains to the students the goal(s) of the lab as well as any background information about the content they need to know (Figure 1). I find this is very important in helping students connect what they are doing to what they are learning. This content can consist of a small amount of new information for the students to learn, or a repeat of old information but provided in a more tangible way that they can apply almost immediately. Figure 1 shows an example of where I provide background information to the students about what alchemy is in an effort to help them connect between the experiment they are doing and an interesting part of science history.

This portion of the handout often also includes the students’ learning objectives, written in a student-friendly way² (Figure 2). This helps the students know explicitly what skills they are acquiring or practicing, and how it ties into the greater curriculum. It can also be helpful to you as the teacher if an administrator walks in to observe you and asks your students what the learning objectives of the lesson are. Of course, students should know their learning objectives in any case, as it is important for making meaningful connections, because the lab process can be a bit of a sensory overload for students (with deductive reasoning happening left and right while students are engaging in ACTION, collecting data, using their five senses, and remembering to document, document, document!)

The first section of my lab handouts inevitably ends with the safety concerns for the activity. This is important for protecting your students and yourself. It is a reminder of what needs to be said and done to ensure that your students are being safe. While I have gotten much better at remembering to tell my students which personal protective equipment they should wear and any specific safety concerns with the chemicals that will be used, I used to find myself forgetting to do so until after the students had already started a lab procedure. Then I would have to halt my classes and state, “Whoops, sorry everyone! Go grab some safety glasses, gloves, and aprons!”

The Pre-Lab section

I use the pre-lab section to assess pre-knowledge of the content the lab is focused on, to review content from the introduction section, and to review information already learned in class. However, in my opinion, the most important purpose of the section is to ask the student to develop a hypothesis about the outcomes of the lab activity itself. In my opinion, students are not really engaging in science if they are not testing something; instead, they are just following basic procedures for the sake of showing they can follow directions and make observations. I find that most of my students do not know what a hypothesis is when they first meet me, regardless of grade level. They always tell me it is an “educated guess.”

To correct this misunderstanding, I spend time working with them to make sure they create a testable statement of what might happen, and make it in the right format. I also stress that it is OK for their hypothesis to be wrong, because good science is not necessarily about getting the “right” answer, but rather following a method to ask and answer questions with precision, and getting results that can be repeated. I even tell them that sometimes being precise with the “wrong” answer is fantastic, because it could lead to a change in an answer to a bigger question.

I know creating a hypothesis for every lab activity can be difficult, but I do find it has long-term benefits for my students’ understanding of the scientific process. A way to make this easier for those of us working with younger students is to utilize sentence stems or starters to assist the students. This is also handy to do with students who are older but still struggle to start such sentences, which can happen with students with certain learning disabilities or who are multilingual learners.

For example, a sentence starter for the steel wool and copper (II) sulphate lab could be, “If I combine copper (II) sulphate with steel wool, then…” In the bouncy ball lab, it could be “If I add more _______ to the original solution, then…” Regardless, I think it is important to remind your students that the hypothesis should be written as an if/then or true/false statement so that the lab is capable of testing it.

In terms of structuring or formatting the pre-lab section of the lab, I often keep it to three to four questions. I do this because I’ve found that when I asked more than that, it often ended up being busy-work style questions rather than meaningful questions. I also found that the more questions I ask in the pre-lab section, the less motivated the students were to do their labs well. So, for the sake of streamlining the process as well as maintaining an effective context for the labs, I keep the number of questions low (see Figures 3 and 4).

The Procedure section

The procedure is both the easiest and the hardest part of a lab for me to write. My goal is to write it as a step-by-step set of instructions in simple, direct English so that students can independently engage in the lab (Figure 5). It is also part of the philosophy of content-first teaching, in which expressing ideas simply so that students can better master the content or applied skill.² Earlier in my teaching career, when I did not understand how to simplify ideas as well, I frequently bombarded my students with vocabulary — unfortunately, before they could really see or understand the meaning of it.

Suffice it to say, they did not perform as well on in-class assessments as my current students now do. Part of what makes the content-first approach to lab activities so difficult, is that you have to put yourself in your student’s shoes and ask yourself questions such as: Do I understand this? Can I easily go from item 1 to 2? Do I have this skill yet? Is this safe for me to do? I often find myself re-writing these sections, especially as the abilities of our students change over the years. As a result, my labs are constantly in flux as the needs of the students change each year.

To help students collect data during the procedure, I embed the collection areas within the Procedures section of the packet and reference them within my writing (see Figure 6 below). I think this makes it easier for the students to track their information, and also best replicates a lab notebook (which I do not use because I use these packets instead). I also feel that mimicking a science notebook benefits the students, since some of them will go on to more advanced courses in college where they will need that skill. The ultimate goal is to replicate what a student might want to create for themselves if they were to compose their own experiments and mirror good procedural practices. This acquired skill set also comes in handy if your students will compete in a science fair.

The Analysis and Conclusions section

I use this section to see a student’s thinking and processing of the lab. I generally average about five questions in this section. I like the students to use it as a place for them to reflect, summarize, and determine their key take-aways from their lab and why it was important for them to do (see Figure 7). If I am seeking graphs from a dataset, the graphs will also show up here, as graphs serve analytical purposes.

When I want to combine a lab activity with a claim, evidence, and reasoning (CER) statement, this is where I choose to place it (see Figure 8). This is because CER writing is very similar to the analytical aspect of the scientific lab process, and I use it to give my students practice with that type of writing while simultaneously getting a lab experience.

Of course, what I find to be the most important part of this last section is whether my students’ hypotheses were supported or rejected based on the evidence they used to support their conclusions. Why? Because this is a large part of what makes them students engaging in real science. They are also learning the lesson that good science does not come from being correct, but rather, from collecting good evidence and drawing accurate conclusions—the correctness of their original ideas is not the important part.

Grading

Grading is the most torturous part of teaching for me. I usually engage in a grading cycle where there is only 24–48 hours between when students turn in their work and receive feedback on it. I am greatly assisted in this by the fact that all of my students have Chromebooks and therefore, I am not fighting the battle of “what did this student write?” but rather, “what are they trying to say?” But, despite my constant engagement in this battle, I can’t help but hate grading lab reports. As a result, I used to have a love-hate relationship with lab activities.

Fortunately, having the students switch from submitting lab reports to the lab packets I’ve described here, and utilizing clear grading rubrics, have been very helpful. The students no longer feel the work is meaningless (after all, how can I give them credit for their thinking if they do not write it down?). In addition, I find I spend substantially less time grading lab packets than I used to spend on grading lab reports. Moreover, it seems more helpful in getting students to fix their mistakes and resubmit their activities for higher credit based on the teacher feedback, which I can now give them fairly quickly. The focus for the lab packet grading is that they are filled out to completion, that they utilize bullets where appropriate (and full sentences where they are not) and, of course, that the content is accurate.

To be most effective in my grading, I have designed my grading rubrics with three parts: the pre-lab, the procedure, and the analysis and conclusions portions — just like the lab packets do. I generally do not grade on mechanics of writing since the students are writing during class, and I am more focused more on their work and their thinking.

Each section of the rubric can be weighted differently throughout the school year, based on what I want the students to focus on and where their skillset is at the time. I do inform the students to always check the rubric as they work on their lab packets, since the allotment of points is ever-changing. For example, I most recently had my students work on a lab to improve their skills calculating the parts of an atom. For this lab, the pre-lab was worth 10 points. But, the procedure and the analysis and conclusions were both worth 20 points each. This is because the focus was on the outcome of the student’s procedural work (as depicted in the dataset shown in Figure 9) and the corresponding analysis. As a result, most of the grade went toward those two sections.

Thus, every time I create a lab’s grading rubric, I have to ask myself: “Is each part of the lab equally as important?”, “What do I want to focus on?”, and “How do I want to allot points to reflect this focus?” For the actual grading, I first decide what full credit for a section will look like, and then determine how to provide partial credit thereafter for work that does not meet that standard. For example, in my Bath Fizzies lab, even though I typically teach it later in the school year, I decided to make all the sections equal in points. The rubric (Figure 10) demonstrates how completing the lab at different levels of accuracy earns students different amounts of points.

I also provide the students with specific feedback as to what they can do to fix their lab and receive more points if they re-submit it to me. By doing this, I empower the students to control their grades, because they can always work toward a 100%. I also have seen an increased turn-in rate since I started to do this.

Conclusions

I believe that lab work brings real world experiences into the chemistry academic classroom. It allows a creative teacher to connect the book learning to real outcomes that students can connect to. It also allows a level of both seriousness and levity in a class setting that can sometimes intimidate students.

I used to be overwhelmed by thinking that labs required complex concepts and hazardous chemicals. Embracing real-world applications, green chemistry, and simplified grading has transformed my labs into an enjoyable experience for both me and my students. It also opened the door to more fun in the chemistry classroom and a less overwhelming experience for me (and my students). Most of my kids love them, and I love how fast the day seems to move and how engaged all my students are.

References

¹ Copper (II) sulphate pentahydrate safety data sheet. Thermo Fisher Scientific, revised Jul 12, 2022. Available at https://www.fishersci.com/store/msds?partNumber=AC197730010&productDescription=COPPER(II)%20SULFATE%20PENTA%201KG&vendorId=VN00032119&countryCode=US&language=en (accessed Apr 28, 2025).

² Sullivan, K. “Using everyday language to teach science may help students learn, study finds.” Stanford Report [online], 2008. https://news.stanford.edu/stories/2008/08/using-everyday-language-teach-science-may-help-students-learn-study-finds (accessed Apr 28, 2025).