Kahoot! Impact: Escaping the STEM “weed-out” trap

Key takeaways

• The mindset of weed-out classes assumes that the toughest survive, but research shows students are more likely to leave STEM because of a lack of support, community, and psychologically safe learning environments, not because of ability.
• When used thoughtfully, tools like Kahoot! can transform high-stakes classrooms into spaces where mistakes are normalized, students stay engaged, instructors have visibility into learning, and confidence is strengthened rather than shattered.
• Lecture-heavy courses don't need full redesigns. Even small active learning strategies can make a powerful difference for who persists, who succeeds, and who sees themselves as capable of thriving in STEM.

If you work in STEM education, you've heard the myth of "weed-out classes." It's the idea that certain introductory courses, especially massive lectures like Organic Chemistry or Calculus, are supposed to be brutal. The logic goes: If you can't take the heat, maybe you are not suited for the field.

But research from across studies exposes how flawed this narrative really is. We're not "weeding out" unqualified students. We're weeding out students who become discouraged by the culture , including many high performers we can't afford to lose.

The high cost of "tough love"

A weed-out class isn't just a difficult class. It's usually a large, foundational class taught through traditional lectures and assessed almost entirely through high-stakes exams.

Across institutions, gateway courses in Calculus and Chemistry courses have an average of 20% DFW (drop, fail, withdraw) rate. Many students repeat these courses, sometimes more than once. The consequences are severe: a single D, F, W, or incomplete in a STEM gateway course significantly raises the risk of a student leaving not just the major, but the entire institution.

Here's where the "tough love" logic falls apart: a study revealed that 26% of students who switch out of STEM had a GPA of 3.5 or higher . Another study pointed out that high achieving women are also more likely to switch out of STEM than male peers after receiving just a single C . These students often leave pre-emptively, not because they are failing, but because they fear they might . Consequently, a single grade from a weed-out class can have a disproportionate impact on their entire career trajectory. As one student in the study explained:

"If I had to say one reason why I shifted [out of STEM], it was my feelings from my performance in that first class that I was not capable of being successful in that major. And that's what it comes down to for me. That I couldn't be successful in that major."

This isn't about ability. It's about confidence. "Grade shock" pushes even strong students to question whether they belong.

From weeds to flowers: rethinking organic chemistry

A 2025 study published in the Journal of Chemical Education (2025) looked closely at one of the most notorious weed-out courses: Organic Chemistry.

Students often describe Organic Chemistry as "drinking from the firehose": a rapid cumulative sequence of concepts where falling behind even briefly can feel catastrophic.

To counter this, instructors introduced active learning strategies using Kahoot! as a formative assessment tool. This didn't require a full course redesign: just small, frequent, low-stakes opportunities for students to check their understanding and for instructors to surface misconceptions in real-time.

The result: a more engaging, responsive classroom with feedback loops that helped students to stay on track.

Students report feeling more engaged and focused in class with Kahoot!

Kahoot! activities were run throughout the Organic Chemistry I and II across fall and spring semesters. Because the quizzes were ungraded , students could participate without fear of penalty.

At first, nearly 30% of students were hesitant to join because they were worried about getting answers wrong. This initial fear highlighted how essential low-stakes assessment is for creating a safe learning environment.

But once the student understood the purpose, the tone shifted:

"I enjoyed the kahoot. I wasn't sure if they were for mandatory attendance or participation for credit at first, and I was worried. But once I learned they were just for review, I tried my best with each question when I did join, and I wasn't as afraid of getting it wrong. This helped me learn."

The impact was clear: 97% of students felt that Kahoot! made the class more engaging . Students reported improved focus, especially in long lecture blocks. They also felt better able to identify what they understood, and what they didn't.

″It was a great way to re-engage the class. It is difficult to maintain focus for long periods, especially in the morning, so Kahoot! helped bring everyone back into focus.″

"With a class of so much specific information, that requires the professor to talk for long periods of time, kahoot quizzes are a good way to invite the students to interact with the lecture. From them, I was able to identify which topics needed to be explained better."

Keeping students on track, not pushing them out

Regular formative assessment counters the belief that knowledge is fixed or that a single poor performance defines ability. Students started to describe their mistakes as information, not a judgment:

"I really enjoyed Kahoot! during class because I would understand the general concepts but then not know how to apply them to a problem. I think that the kahoots really bettered my understanding of the material and helped prepare me for the tests."

Kahoot! also helped students confront misconceptions early rather than discovering them during an exam:

"…Kahoot! made it difficult for me to lie to myself about the depth of my understanding during lecture, which I greatly appreciated. I think Kahoot! prepared me to answer quiz and test questions."

For instructors, these quick checks made it possible to address misunderstanding immediately, before they snowballed into lost confidence.

Research re-affirms impact of active engagement on learning outcomes

The pattern seen in this study on Organic Chemistry course isn't unique. Across STEM disciplines, studies show that when students engage in low-stakes, interactive learning, outcomes improve and more students persist.

A study in Chemistry found that regular Kahoot!-based practice was associated with higher final exam performance and a meaningful increase in course pass rates. In Engineering classrooms , even small incentives built into Kahoot! activities boosted participation and students who participated consistently performed better in exams. And in medical education , from nursing to pharmacology, students reported that active learning with Kahoot! helped them stay engaged, understand concepts more deeply, and feel more confident in high pressure subjects.

Together, these findings help us understand how to design STEM courses that support learning through active engagement, real-time feedback, and a classroom culture where students can grow rather than be filtered out.