DW: It becomes a math issue. Here’s what I mean by that: When you give lab assignments, and students have questions or get stuck, the more people there are in the class, the longer the “help line” becomes. In a learn-to-code program, you cannot move on if people are still struggling with a topic, so now you fall behind the scheduled pace.
Having a second instructor in the course can mitigate this issue, but then you’ve erased any savings you were trying to achieve.
Also, the larger the class size, the less the group tends to bond. Ideally, you want students to become a cohesive, supportive unit that works together and helps each other. They are learning how to function as a software development team.
Smaller cohorts tend to build a tighter sense of community and have more robust class discussions. They talk about different ways to solve problems. The ability to listen to others’ perspectives and weigh the merits of different courses of action are vital soft skills that learn-to-code participants need to cultivate.
Further, some people are uncomfortable speaking up in a group, and the larger the class, the harder it is for these individuals to ask questions and seek help.
For these reasons, I strongly encourage learn-to-code sponsors to cap classes at 20 participants.