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Before becoming a high school chemistry teacher, I served in the United States Army for 21 years, specializing in field artillery and electronic warfare. During that time, three of my sons took high school chemistry classes that they despised.

As I had thoroughly enjoyed my own high school and college chemistry experiences, even earning a bachelor’s degree in it, I was sad to see my sons’ reactions to this important class.

Witnessing their frustration over the years eventually drove me to pursue a second career as a high school chemistry teacher after retiring from the Army. I wanted to build a better classroom environment than what my sons had experienced.

I wanted students to enjoy science and to walk away at the end of the year feeling like they learned something useful for their lives and future careers. I hoped that—maybe—my own passion for chemistry could help make it a better class than those my boys had taken.

Unfortunately, even during my first years of teaching, I continued to hear students tell horror stories about their chemistry classes. And they generally claimed to have only taken chemistry to get the last of the science credits they needed to graduate. All I could think was, “It doesn’t have to be this way!”

Shaping a Teaching Philosophy

I recognize that my experiences with my sons and my students may not represent the larger population of chemistry students, but it is distressing to me to witness such negativity—in any student—toward a subject that I find so fascinating and useful.

As the central science, I see chemistry as a vehicle to developing critical thinking skills and to setting students up for long-term academic success.

Since deciding to pursue teaching and throughout my first few years of practice, I’ve been developing something of a personal teaching philosophy. I want chemistry to be more than just a graduation requirement for students. I want chemistry to be something students notice with curiosity throughout their days.

Based on these goals, I’m working to anchor more chemistry concepts in real-life examples with clear and meaningful connections for students. I try to encourage student curiosity by capturing those “teachable moments” when students ask about phenomena they may have seen in a video or even experienced in their lives. And I will keep looking for interesting ways to provide students with critical thinking opportunities throughout all aspects of classroom learning.

It’s my hope that, by continuing to refine this teaching philosophy, I can help transform chemistry for my students from a grudging requirement to a positively anticipated experience.

Building Questioning Minds

My goal on the first day of school is typical of many chemistry teachers’: I want to represent chemistry as a class that requires active engagement and thinking. Each year, I choose a few demonstrations to get students thinking and questioning right from the start.

One demo I especially like involves what initially seems to be a boring observation of a candle. On the first day of school, I show two “candles.” One is actually a candle, and the other is a potato that I’ve shaped into a candle with a modified wick. (Some may prefer to use an apple instead of a potato.) A cashew wick works best, but sometimes students have nut allergies—so I avoid this and just use a regular candle wick in the potato.

I place the two “candles” in the front of the room, and students write observations about them. Then they continue recording observations as I light both candles, let them burn for a few moments, and then blow out each flame. At that point, I ask a few students to summarize their observations for the class.

I can always count on a handful to say something like, “The candles are made of wax,” to which I reply, “How did you observe that and what led you to make that determination?” I then take a bite of the potato candle, ensuring the students hear the crunch as I chew!

This unexpected act promptly challenges the assumptions they made in their observations, paving the way for a bit of metacognition and readying their minds to figure out where they went wrong and how to not make the same mistake in the future.

It’s been a great way to start building the culture of curiosity that I try to nurture throughout the year.

Chemistry Connections in Their Feeds

On occasion, students will ask me to explain something they saw in a TikTok video or YouTube short. Instead of just answering the questions directly, I like to facilitate a class discussion where students use what we’ve covered in class so far to try to explain it to me.

My favorite example to date is when a student asked about an “exploding gummy bear” video they had seen on social media. This question came up right before we began studying chemical reactions—so luckily it fit naturally into the scope and sequence. The students’ curiosity was strong enough that I decided to move combustion reactions from the end of the unit, as was my normal sequence, to the beginning.

We discussed what students knew from the video and how their hypotheses might explain what was happening in the video. While trying this experiment would be above my safety threshold for a class of 28 students, I was able to safely perform it the next day—as a teacher demonstration behind a safety shield and under the fume hood.

My students documented the entire experience as an experiment in their lab notebooks. The “a-ha moment” happened when students realized the sugar in a gummy bear was a fuel, just like gasoline in a car’s combustion engine. They eventually questioned what the reaction products might have been, which led to a brief discussion of complete vs. incomplete combustion.

The other part of the reaction—decomposition of KClO₃—was briefly mentioned, and I explained we’d study that type of reaction later in the unit.

Beginning the unit with an exciting demonstration was a much more interesting way to introduce combustion reactions than I had originally planned that year. So I’ve since added the gummy bear demo to my yearly plan. (However, I’d caution each teacher to thoroughly study the safety precautions and only try the demo if you and your classroom are properly equipped to manage it safely.)

Rethinking the Lab Notebook

During my own time in high school, I remember doing laboratory work every week in chemistry class. Though labs and experiments require significant teacher preparation and oversight to ensure student safety, I believe frequent experiments are worth it and will help students stay engaged with chemistry concepts.

At the beginning of my teaching career, I noticed that many chemistry teachers had abandoned traditional laboratory notebooks in favor of fill-in-the-blank worksheets. With these, I saw students racing to complete all the blanks and submit quickly, rather than taking time to explore the science—which made me question their efficacy.

In “Assessing Science Practices in Undergraduate Chemistry Laboratories: Why We Need to Do Better—and How We Should,” the authors suggest that instructors can better assess the quality of students’ science practices by both directly observing their work and evaluating their written communication.

I’ve found that requiring students to keep a lab notebook supports both of these—observation and written communication—while also striking a balance between cookbook-style lab handouts and inquiry-based practice.

Students first learn the “how and why” of keeping a scientific notebook. We discuss general contexts where recordkeeping can have legal implications and how precisely recording certain types of information is common in a variety of fields—not only in science.

To mimic a real-life scenario, I do require that they write in pen and use the traditional methods of acknowledging mistakes (Figure 1) so they learn that mistakes are allowed and can be learned from.

Figure 1. Excerpt from a student’s notebook, studying the “Heats of Evaporation” for different compounds that contain different intermolecular forces. Note the crossed-out sections, initially with improper formatting (scribbled out) and the additional use of a single line to designate a mistake.

Using as a foundation the laboratory report rubric from the Chemistry Solutions article "Tools and Strategies for Teaching Lab Report Writing", I modified the sections to create a standard rubric for my classes. Students use this rubric all year to guide how and what they document (Figure 2).

Figure 2. Modified rubric for students to complete their lab notebooks. Students receive a hard copy on the first day of school, but this is also loaded into Google Classroom for students’ reference.

With the customized rubric, I can tailor the directions for each lab to emphasize appropriate science practices while maintaining a consistent format for what must be recorded. I provide significant scaffolding at the beginning of the year, scoring only specific sections in early labs so students can build skills in a low-threat environment.

I still struggle to avoid the “just copy everything” approach that the students naturally gravitate toward. I recently tried a few different strategies with the lab instructions to combat this minimal-thinking practice.

One simple way is to provide the instructions on paper and then give slight modifications verbally. This gives me an easy way to check for students who blindly copy the incorrect procedure. Sometimes I also provide certain details during our pre-lab discussions that are not written on the handout and then look for the relevant documentation in the lab notebooks.

As a more proactive way to promote thinking, I regularly encourage students to sketch equipment set-ups (see notebook entry in Figure 1) and to use labels to show details instead of copying the written directions for the same set-up.

I continuously search for additional strategies, as I’d like to find ways to better promote thinking throughout every phase of the lab experience.

Talking It Out and Writing It Down

For me, facilitating dynamic discussions and lectures was—and sometimes still is—the most challenging teaching method because an important goal of mine is for students to learn in truly engaging ways.

During my first year, I included many activities where students read and learned chemistry with minimal teacher involvement. This was a recommendation from a teacher training program I attended, but it rarely engaged the students—who found other ways to entertain themselves and couldn’t demonstrate mastery of the concepts afterward.

In my second and third years, I began moving away from this practice, instead leading class discussions and randomly calling on students to demonstrate various concepts throughout these talks.

Now, in the early months of each school year, I work hard to create a non-threatening environment—even telling students I prefer wrong answers, since we learn more from mistakes than from getting it right the first time! This is meant to reduce the anxiety many students feel when asked to explain their thinking out loud.

With this discussion-based practice, a student might explain their understanding of a system, like the electrostatic interactions within an atom, or they might talk through the steps they took to work through a stoichiometry problem.

Sometimes I ask the class to use what we have just discussed to try explaining something new. For example, while studying gas laws, I might ask them to explain why tire pressures change in different temperatures.

Seeing how their peers process chemistry concepts has been helpful for my students, but there is still lots of room for improvement in building strategies that promote student concept retention.

And so I continue exploring. I expect that this will remain an evolving effort each year.

Another promising strategy to facilitate more engaged learning during my class lectures is the “sketch notes” technique. This form of notetaking can help students take more effective notes by combining visual drawing with traditional methods to highlight main points, group ideas, and record questions.

After learning about sketch notes at a science education conference, I tried it during my nuclear chemistry unit at the end of last year. On the end-of-year survey, many students reported really enjoying the sketch notes technique to learn chemistry.

In this new school year, my students are using this strategy in their class discussion notebooks. I provide students with a daily template (see Figure 3), which they fill in with pictures and notes to show how they make sense of concepts covered in class. Regularly checking these notebooks allows me to formatively assess their understanding of class discussions.

Figure 3. Sample template created by the author, for teaching students how to use sketch notes

Using the sketch notes technique means students engage with a concept by listening to it, writing it, and drawing pictures to represent it. This does slow down the pacing of class, at least while students are learning the process, but I’m hoping it will also increase concept retention.

An Ongoing Quest

Finding unique and innovative ways to teach students chemistry is a worthwhile endeavor. As a central science, chemistry is everywhere we look, and every student needs a basic understanding of science.

As a relatively new teacher, I don’t think one right answer exists as to “how to teach chemistry.” I try to be flexible in my approaches and to adapt to the students in the room. Sometimes they’re good with just textbook instruction, but other times the chemistry needs to be dialed up and related to their everyday lives to make a connection.

I like to change things up from year to year and even shift plans as the year progresses. With each adjustment, I’m looking for new ways to improve student learning, but I’m also hoping to boost student engagement—while nudging them toward actually enjoying chemistry.

My overarching goal is that students walk away from my chemistry class having learned more than just the topics—and, ideally, looking back on their time there positively.