It is normal for a student to have questions during a lesson. What isn’t normal is for the student to ask them. Students don’t ask questions because they don’t expect the topic to make sense or they don’t expect the teacher to explain the answer to them in a way that makes sense.

However, because so much of Petri Dish is grounded in a set of local mechanisms that players can understand intuitively, it sets up an expectation within the player that things in Petri Dish can and should make sense. They get in the habit of drilling down to local mechanisms and the molecular scale, figuring things out for themselves. And it is going to bug them when something isn’t equally grounded.

For example, all the player knows about proteins from playing the game is that proteins are assembled out of amino acids, and they selectively grab onto molecules and do work on them (either transporting them or recombining them to form new molecules) using energy from the cell. The player is going to apply that understanding dozens of times a day to solve problems, yet she doesn’t understand the underlying mechanism as well as she understands other mechanisms in the game. And nucleotides behave in the same way! How? Why? The answer to these questions is going to feel like the key to opening a bunch of new and important doors to her.

Petri Dish is designed to elicit questions, but we aren’t deliberately withholding relevant facts from the player and being coy. The player learns what she needs to know about proteins by observing them. She doesn’t need to know about protein folding and binding sites. Zooming into the molecular scale will reveal protein folding and binding sites to her, but not how they work. To understand protein folding and binding sites, she would then have to know about chemical bonds, polarity, electronegativity, valence electrons, and much more. Knowing these things would obfuscate what she really needs to know about proteins to solve the complex problems in Petri Dish: that proteins are assembled out of amino acids, and they selectively grab onto molecules and do work on them (either transporting them or recombining them to form new molecules) using energy from the cell.

Knowing more details would temporarily make proteins less concrete for her and make her feel like we were pulling a bait-and-switch by tempting her with a game, but then making her learn a bunch of stuff she doesn’t actually have to know to play first. And proteins aren’t the focus of Petri Dish; understanding the cell as an integrated system and how local mechanisms can lead to complex global behaviors are.

In this specific instance, we feel it is better to give the player an abstraction that she can use and manipulate intuitively first, and then fill in the blanks later — once she has a framework for proteins in her mental model — through a series of teachable moments. And if that doesn’t happen and those questions don’t crop up, then we know that we are doing something wrong.

We plan to include supplementary materials with Petri Dish covering the most common questions that will arise. When used in a classroom setting, we see Petri Dish generating lines of inquiry from students that drive investigations and deeper study in cell biology topics.