A Tale of Two Science Students

Inquiry learning versus direct instruction — what’s the difference?

I.

Brandon’s looking forward to chemistry today. There’s going to be another lab activity!

He gets in his small group and reads the procedures in the “Kool-Aid Lab” packet. Apparently, his group members need to get three cups to fill with equal volumes of water and varying amounts of Kool-Aid powder.

Brandon, the bright go-getter of the class, divides the tasks among them. Once all the cups have been filled with water, one cup receives with the standard amount of Kool-Aid powder; one groupmate writes “1 M” on it in neat Sharpie. A cup with twice the concentration reads “2 M,” and a cup with half reads “0.5 M.”

Brandon and his group members record their observations. The more Kool-Aid is dissolved in the cup, the redder the drink. They take a sip of each, noting that the 0.5 M Kool-Aid tastes weak while the 2 M Kool-Aid is disgustingly sweet. Now the packet says it’s time to form hypotheses—in other words, time to do science like a scientist!

“How do you think the concentration of the Kool-Aid affects its pH?” Brandon pauses. No responses. After all, it’s not as if the class has been taught this. “I think that higher concentrations of powder make it more acidic. I mean, the 2 M Kool-Aid tasted pretty strong, and I think it has Vitamin C, which is an acid. So, higher concentration leads to lower pH?”

The group nods.

“Okay, let’s write that down. Next question. How do you think the concentration of the Kool-Aid affects its boiling point?”

His groupmate looks up from the Google search on her phone screen. “It raises it.”

Brandon jots that down. “Sounds good. Now let’s get the pH indicator strips and the hot plate for the next steps.”

Unsurprisingly, the group’s hypotheses are confirmed. Brandon is pleased. He got it set up efficiently, he communicated effectively, he worked actively, and most important of all, he had fun—perhaps he should go into science someday!

II.

Aaron is looking forward to chemistry today. He feels his mind expand in that class every day.

Today, the lesson is on concentration. Molarity, the teacher says from the front of the room, is the number of moles of a solute per liter of solvent. She provides a sample calculation, and the class does a few practice problems to get this concept rock-solid — first finding a solution’s molarity from moles and liters (a straightforward calculation), then finding molarity from grams and liters (which takes a little more thought, but they’ve already had lots of practice converting grams to moles), and finally finding molarity from kilograms and cubic centimeters.

The teacher goes over the solutions step-by-step. It all makes sense to Aaron. He fixes his little mistakes, but overall, thanks to the thorough teaching, he didn’t make many in the first place.

The teacher moves on. Molality is the number of moles per kilogram of solvent. Again, the class does some molality practice problems of increasing complexity and goes over the answers.

Aaron is in his own sweet spot — he’s not bored, not overwhelmed, just focused and growing, plugging and chugging the numbers, just like most of today’s successful chemists did in their own school days.

The teacher explains that molarity affects conductivity, reaction rates, and pH, whereas molality affects freezing and boiling points; the class will learn how to solve for those within the next few weeks. Aaron is the curious, sciencey type, so this piques his interest. If math is the language of the universe, physical and chemical formulas are like the grammar, he’s realized. Maybe becoming a chemist someday would be fulfilling.

III.

“What a day that was in class! Your learners were all so engaged,” says the district classroom observer to Brandon’s chemistry teacher. “I’m here to ask you a few questions for the evaluation.”

The teacher smiles. “I’m ready.”

“What would you say is your main approach to designing lessons?”

“Well, the way I see it, I don’t teach science lessons — I teach budding young scientists. And scientists don’t sit around memorizing facts. Obviously I do make sure I meet the curriculum requirements, but I’m always trying to do it in a way that involves creativity and curiosity. I’ve heard that just telling them ‘this answer is right, that answer is wrong’ can kill those skills, and that’s not the way to do it in a world where we need more innovative problem-solvers than ever. They need to learn things for themselves instead of being spoon-fed.”

The observer is stunned. “Excellent way of putting it. That’s exactly what I saw today.”

IV.

“What do you believe are your strengths as an instructor?”

“I’ve gotten a lot better at behavior management.” Aaron’s teacher thinks back to when rowdy teens who didn’t want to learn chemistry would act up and prevent everyone else from learning. It sure isn’t like that anymore! “It was hard at first to control the class when I was so nervous, but with experience, I gained the confidence I needed. Thankfully, they all know not to get disrespectful now!”

“Oh, yes, that’s always important.” The observer types notes on a laptop. “But how do you ensure the class is engaged?”

“I have a no-phone policy, and they know it. I have no qualms saying give me your phone. And when we do practice problems, it’s silent. I’ve learned that if they chat, someone’s always going to distracted by off-topic conversations. It’s harsh, but it means all eyes are on me during lectures and all the work gets done.”

“Have you considered including more active learning? You know, making the class less drill-and-kill and more student-centered?”

Aaron’s teacher wants to sigh. Here we go again. After working so hard not only to learn the science, but to get good at managing dozens of students at a time and making sure they’re all learning the science, people who aren’t doing her job still have the nerve to say she’s not doing enough?

V.

Fast forward years later, and Aaron and Brandon have just started college; their chemistry teachers both wrote them sparkling letters of recommendation. They’re now sitting in a lecture hall, listening to their professor for introductory chemistry.

It’s a far cry from the engaging activities that Brandon got in his high school chemistry class, but Aaron sure is engaged. As he takes notes, his focus stays on the the slides up front; the periodic impulse to zone out or check his phone doesn’t tempt him.

Brandon, though? His mind keeps wandering. Sitting still and listening passively doesn’t fit his learning style, he thinks. Heck, he wonders how anyone could learn best this way. He’s watched a popular YouTube video saying that this “factory model” shortens attention spans and stunts natural thinking abilities. His chemistry class back in high school was different; it trained him to be an independent problem-solver!

That afternoon, they get started on their homework assignment. Aaron paid attention during the lecture, and he understood it well because it echoed what he was taught years ago, so he easily figures out what approach to use for the problems. A glow of satisfaction comes over him; he’s in his element.

When Brandon looks at those same problems, he doesn’t get it, and no creative problem-solving strategy can help him here. Before today, he would’ve said that knowing facts by heart has little value in an age when you can “just look things up,” but the stress of having to think through a problem using freshly crammed information from three different tabs is making him reconsider.

Lectures, homework, labs — for the rest of the year, both these bright, motivated chemists-in-training get exposed to new concepts and realize they have a lot left to master. Only for Aaron, this idea is thrilling. For Brandon, it’s worrying.

VII.

Yes, this is just a story.

Yes, there is considerable evidence that directly guided instruction leads to better learning than inquiry-based methods.

I wrote this in response to those who think surely inquiry learning has to boast better outcomes — it’s engaging! It’s active! It’s like what real scientists do! In reality, it doesn’t teach the content well enough, nor does it cultivate the quiet, disciplined nature of higher learning, and that can lead to difficulties later on, difficulties that quality direct instruction can prevent. I hope I’ve illustrated reasonable causal relationships here. (Bear in mind, the Kool-Aid lab is real. Except the version I did in high school had even less scientific content.)

If you think I presented inquiry learning unfairly, just know it could’ve been worse, according to the Kirschner, Sweller, and Clark paper linked above:

Hardiman, Pollatsek, and Weil (1986) and Brown and Campione (1994) noted that when students learn science in classrooms with pure-discovery methods and minimal feedback, they often become lost and frustrated, and their confusion can lead to misconceptions. Others (e.g., Carlson, Lundy, & Schneider, 1992; Schauble, 1990) found that because false starts are common in such learning situations, unguided discovery is most often inefficient.

I could’ve depicted Brandon confused, so focused on following the directions and getting precise measurements that he doesn’t absorb any of the underlying science behind his observations. I could’ve depicted Brandon’s group getting anomalies in their measurements and thus not even learning the science concepts. I could’ve depicted him wondering why the teacher couldn’t just teach them the relationship between concentration and pH or boiling point instead of “making us do all this work.”

The fact that Brandon enjoys it, ostensibly develops useful skills (communication, collaboration), and ends up going into university-level chemistry makes inquiry learning look pretty good. It only turns sour when he’s forced to confront what he can’t do.

I believe the goal of science education is to empower students with foundational scientific knowledge, and direct instruction is consistently found to be the best way to do this, so as a science person, I support direct instruction in pre-university science classes. An upcoming post of mine will address laypeople’s common criticisms of direct instruction. Thank you for reading!