Improving online class discussions with AI characters

A quick demo of a powerful idea made possible with custom GPTs.

I have a confession to make... I don’t really like online discussions. In fact, I hate to say it, but I think they can often become (gulp) kind of a waste of time - for both students and faculty.

Now, don’t get me wrong - I do frequently use discussion boards in my online astronomy classes. I work really hard to make them interesting and engaging. One week students will craft a eulogy for a star that has died, and another week they will go shopping for meteorites online and report back what they would purchase.

But even so, I know that even despite my best efforts, the online discussions in my class can often become busywork for my students, and the interactions with their classmates often don’t add as much value as I would like.

Making online discussions come alive with AI characters

I recently encountered a great idea from Prof. Richard Epps of Imperial Valley College. He’s been experimenting with using custom GPTs to create simulated discussions in his political science courses.

In these discussions, the AI takes on the role of several different characters or personas including historical figures, fictionalized classmates, and the professor himself. The student then interacts with these characters, having a very real discussion with these simulated characters.

Inspired by Prof. Epps work, I built my own character-driven simulated discussion centered around the classic astronomy debate topic, “Are we alone in the universe?”

How I built the custom GPT?

My AI tool of choice is ChatGPT, so I logged into my Plus account (yes, I’m sorry, creating custom GPTs requires a paid account), and went to the GPTs page. OpenAI hosts a wide variety of user-created custom GPTs, but you can also create and publish your own.

When you start creating a custom GPT, you will encounter a familiar chat-style interface where you can simply start talking with ChatGPT, defining the behavior of your custom chatbot. As your conversation progresses, you will move over to the “configure” page, which contains a premade set of instructions based on your chat.

Creating your own custom GPT is intuitive and user friendly.

While you are editing your instructions, you can continuously test and refine the GPT in a preview window to the right of the screen. It takes time to get everything working just the way you want, but there is no coding required - everything uses natural language in just the way you would expect from a modern AI chatbot.

My instructions explained the goal of my chat bot. I wanted to facilitate a conversation between the user and several simulated characters. I wanted to include dynamic and interesting personas in the discussion, so I tried to be a little extra creative. Here are the four personas that I created.

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- Morgan: A skeptical astrobiologist focused on statistics and scientific rigor; dismisses intelligent alien visitation as unlikely.

- Ari: An enthusiastic astrochemist focused on organic molecules in space and the likelihood of microbial life.

- Rory: An AI researcher who believes extraterrestrial contact will come from artificial, not biological, intelligences.

- Taylor: An alien disguised as a human, who speaks in odd metaphors and misuses human vocabulary in amusing and strange ways.

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I had to experiment for 30+ minutes with the instructions. At times, the personas would just go on talking to one another without asking the user to chime in. Other times, the conversation would stop abruptly. After playing with the instructions and repeatedly testing the GPT, I was able to get to a tool that worked reasonably well. (You can view my final custom GPT instructions here.)

I personally find the simulated discussion to be quite engaging. I tried it several times, sometimes acting as an engaged student who pushed the conversation deeper, and other times trying to derail the conversation with my confrontational language. It’s fun to see how the professor and fabricated personas react to the students comments in unexpected and original ways.

I encourage you to try my simple simulated discussion demo to see what it is like (you will have to login to a free ChatGPT account to use it) or watch the video below to see how it works.

At the end of the discussion, the simulated instructor offers to give the user feedback on their performance using a simple rubric. There’s no simple method for integrating this scoring into an LMS grade book, but it highlights the unique potential for custom GPTs like this to provide highly personalized formative assessment and feedback to each student quickly and easily.

Why I think this is worthwhile

The use of simulated discussion with AI characters adds value to students in a couple of specific ways.

1. It’s synchronous
   One of the great challenges of traditional online discussion boards is that the are asynchronous, so any interaction with classmates is disjointed. The simulated discussion allows the student to interact with the characters in a smooth, natural, and synchronous way that increases engagement (and I believe educational impact).
   

2. It’s personalized and private
   Traditional online discussion boards are very public - generally all of the students can read one another’s posts. By contrast, this approach allows each student to have a private conversation with these AI characters, exploring their own ideas freely without fear of what their classmates may think.
   

3. It promotes more “authentic” debate
   It seems silly to describe communication with a chatbot as “authentic,” but hear me out. Interacting with other students in an online class can sometimes be… well, boring and inauthentic. Students often have similar perspectives on the prompts and drift toward the dreaded “I agree” response. By including AI characters who may have very different (or even controversial) opinions, students can engage in vigorous discussion and debate with someone they truly disagree with (and without fear of hurting their feelings or coming across as harsh). I would argue that can provide a level of authentic debate rarely seen in traditional online discussion boards.
   

4. It’s fun.
   Students can play and experiment in these simulated discussions. They can try to outsmart the expert, insult the professor, or share their most outlandish ideas. They get to roleplay and see what happens. It’s fun. (Seriously, try the simulated discussion tool for yourself and see if you can get in trouble with Prof. VH.)

A possible improvement

I am always hesitant to push my online students out of the LMS and into a third-party tool, especially one that requires them to create an account. I find it introduces potential confusion and technical issues for students, which usually ends up causing more frustration for them (and more work for me).

If I were to implement this in my own class, I would experiment with an automation that uses the APIs from Canvas and OpenAI to add an AI character to the existing discussion board that is native to the LMS. I could schedule the automation to run daily and respond to each student in the discussion board, having a back-and-forth with each one for all to see.

The upside is that students could interact with the AI character inside the LMS, and I could still use the native grading and feedback tools. The downside is that the discussions would be public and asynchronous. Hmm… I don’t know if this is ultimately an improvement or not.

Using other platforms and tools

Of course, you’re not limited to custom GPTs from OpenAI. In particular, Google’s Gemini has a similar feature called “Gems.” I tried using my same instructions in a custom Gem and found that Gemini had a harder time understanding what I was asking for. As a result, the conversation would get stuck in doldrums where no one was talking. As the user, I would have to revive the conversation with an occasional, “So, how about those aliens…” No doubt I could eliminate these issues with further refinement, but ChatGPT was already working for me, so I moved on.

It’s also worth noting that Meta has invested heavily in creating customizable AI characters. While these tools currently have the greater adoption outside of the US (via WhatsApp), I think we will see these AI characters becoming more accessible and commonplace in the months ahead via Meta’s family of apps.¹

How would you use AI characters in your content area?

In Prof. Epps’ class, students were invited to discuss the civil rights movement with Thurgood Marshall and Martin Luther King Jr.

In my astronomy class, I imagine students having a vigorous debate with Ptolemy, trying to prove to him that our solar system is sun-centered instead of earth-centered.

But what about your content area? What ideas do you have for AI characters that you could invite into your class discussions? I’d love to hear your ideas in the comments.

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1. These statements about Meta are based on the April 30, 2025 Dwarkesh Podcast interview with Mark Zuckerberg.