High school students delve into theoretical computer science
The seemingly simple question that Princeton computer scientist Bernard Chazelle posed to students turned out to be a doozy.
“How many security guards does it take to police this mall?” he asked, drawing, on a classroom chalk board, a building with a number of different wings. “You need to hire guards, and the guards need to see all parts of the mall at any given time, but one guard can't see everything.”

For the next hour, the students, most of whom were in high school, proposed ways to answer Chazelle's question, using concepts from mathematics and computer science typically taught only to college students.
The students, who included four university undergraduates and 16 high school students, were attending the Summer Program in Theoretical Computer Science at Princeton. The program, intended to boost high school student interest and ability in computer science, was sponsored by the National Science Foundation through the Center for Computational Intractability, a multi-institution center that explores the most difficult theoretical problems in computer science.
The students came from New Jersey, California and India to attend the program, which ran from June 22 to August 12.
“It's a great opportunity for these students,” said Moses Charikar, professor of computer science at Princeton and member of the intractability center who helped organize the program. “We give them a friendly, inspiring environment to work with other students who share their interests and to learn from top-notch computer scientists.”

During the program the students attended daily lectures taught by Rajiv Gandhi and Tejas Gandhi, faculty members at Rutgers University-Camden, and guest lectures by computer scientists affiliated with the Center for Computational Intractability. In addition to Princeton and Rutgers faculty, researchers from the Institute for Advanced Study and New York University are affiliated with the center.
The summer program at Princeton grew out of informal lectures on computer science that Gandhi began giving on weekends in 2009 at Rutgers University-Camden to Cherry Hill East High school and Haddonfield High school students, and a similar program hosted at Rutgers-Camden last summer. “I've learned that high school students can grasp college-level topics in computer science, and that they are very interested in learning,” Gandhi said.
During the program, the students studied a range of topics related to Theoretical Computer Science, including Discrete Mathematics and Algorithm Design, covering the equivalent of two introductory undergraduate courses in computer science.
In his lecture Chazelle, the director of the Center for Computational Intractability, taught computational geometry, an area of computer science that deals with algorithms that use geometric concepts to solve problems. His question about how to calculate the number of guards needed to police a mall served as an introduction to the basic concepts of this field.
“It's been an amazing opportunity, “ Henry Liu, a recent graduate of Princeton High School who attended the course, said after Chazelle's lecture. “It really teaches you how to think in a different way, to solve problems critically.”
Anusha Chheda, a high-school sophomore from Mumbai, India, who decided to attend the program after attending lectures by Gandhi in India, said the program changed her perceptions about computer science. “I first thought computer science only related to computers, but really it's about logic and thinking,” she said.
Based on the success of this summer's program, the Center for Computational Intractability is considering offering the program next summer. “This gives the students a sneak peek into what they might study in college and shows them that there is a lot of theory behind the computer applications they use every day,” Charikar said. “This year was an experiment, and it was a great success.”
