The 55 students hired this spring to serve as either course assistants or undergraduate learning assistants for CS50’s second showing at Yale have spent the last three weeks learning to make s’mores and craft airplanes out of Legos, all in preparation for instructing fellow undergraduates in more complex computer science theorems next fall.

Absent from these training sessions, however, is computer science professor Brian Scassellati, who served as CS50’s lead instructor last fall. Scassellati has not participated in training because he will not be teaching the course next fall.

Currently, there is no instructor set to teach the class, but according to Computer Science Department chair Joan Feigenbaum, the department is “right on the brink” of choosing his replacement.

Despite Scassellati’s absence, students currently being trained for their new jobs said they had positive experiences with the training. This year, 55 ULAs and CAs were hired -— a near 10 percent increase in comparison to the 47 students who taught last fall.

“One of the goals for spring training is to not only prepare staff members to be good instructors in the course, but also to build a culture of staff accountability and enthusiasm,” head teaching assistant Andi Peng ’18 said.

All new hires had to undergo the same two training sessions in the past three weeks, each eight hours long. In addition, the new staff will also need to complete all of last semester’s problem sets “perfectly” before the start of the fall term, according to Peng.

The first training session focused primarily on teaching the new staff how to interact with their students, instruct productively and provide helpful feedback, said Stephanie Hickman ’19, who will serve as a course assistant next fall.

Hickman said the first section started off lighthearted.

“[The idea was] if we could teach things like [s’mores and Legos] it would make it easier to teach more complex CS principles,” Hickman said. “We started with easier things in the first training, and in this second [session] we taught the more complex theories that are in the problem sets.”

But the sessions did not focus only on teaching — the new staff also met with a student improvisation group to explore the connection between improvising and being a teaching assistant, new ULA Saran Morgan ’18 said.

“When you are in improv, someone proposes an idea and as the scene partner you have to say yes and add to it,” Morgan said. “In teaching, you should do that as well — accept ideas from students and just try to help them from then on. It was very much about appreciation of other people’s ideas and ways of thinking about things.”

The innovative culture behind CS50 attracted a large number of students to apply for the position, Hickman said.

According to course head Jason Hirschhorn, the course received a large number of applications from students with a variety of backgrounds — both CS50 students and non-CS50 students, as well as CS majors and nonmajors, applied to serve as teaching and course assistants.

Hickman said the application process was “a little intimidating” given the number of students who wanted the position.

In order to apply, students had to first submit an application, and those chosen then underwent an interview process during which they had to act as if they were hosting office hours, with Hirschhorn pretending to be a confused student.

Now, Hirschhorn is tasked with leading the training sessions, alongside three other course heads.

CS50 lead instructor at Harvard David Malan said the CS50 staff is still in the process of reviewing the results of the fall 2015 course in order to make any necessary alterations to the fall 2016 offering.

But he added that some aspects of the course “worked so well” that they will become a time-honored part of the class in New Haven this fall.

Whereas last year CS50 Puzzle Day was held at Harvard for both Harvard and Yale students, this fall the staff plans to host events in parallel on both campuses so more students can participate in the tradition.

“Now that CS50 has an institutional memory here at the university, we expect the second year to run a lot smoother than the first, with students and staff alike both aware of what exactly the course is and what it entails,” Peng said. “Hopefully, we can continue to build on this incredible program and offer students an even better course this upcoming fall.”

Over 400 undergraduate students took CS50 in its first offering last fall.