How does TikTok know what you like? Northeastern graduate students teach high-schoolers about power of algorithms

Photo by Matthew Modoono/Northeastern University

From the ease of facial recognition technology to the excitement of TikTok, algorithms have offered the modern world many comforts and advantages; however, these softwares can also pose threats to privacy and security if not designed with care.

This is the lesson four graduate students in Northeastern’s Khoury College of Computer Sciences sought to instill in high-schoolers this summer through “The Power of Algorithms,” a course they designed as part of SMASH Northeastern. 

The three-year, tuition-free, college-prep program allows students of color, who have historically been underrepresented in STEM, to study an array of science- and tech-related subjects so they can pursue a career in the field. The program is funded in part by Akamai Technologies, which also works with Khoury College to provide out-of-class experiences to the young scholars, who live on the university’s Boston campus.

The Power of Algorithms, a computer science elective, was among the electives offered to this summer’s cohort of SMASH scholars. Designed by master’s students Jianhua Che, Lauryn Fluellen, Mariah Maynard and Dr. Shriya Dhaundiyal, the course centered on the apps and websites people use in their daily lives, the algorithms that fuel these programs and the effects of these technologies, both positive and negative.

“The basic aim of this elective was to show the power algorithms hold and teach students how they can build these powerful tools,” Dhaundiyal says. “We also wanted to show that there are consequences with this technology when it’s not thoughtfully designed.”

How it all came together

Preparations for the course started in April, with the graduate students meeting bimonthly with Laney Strange, a computer science professor and director of broadening participation, who helped guide them in their lesson planning. After two months, they fit the class to meet the hour and day requirements of the SMASH program and made the curriculum comprehensible for the young scholars to learn within two weeks.

That meant the four students would each teach a different algorithms-related subject to the high-schoolers on each day of the two four-day sessions. On the first day, Che gave the SMASH scholars an introductory crash course on search algorithms, explaining to them the two types of search algorithms used in the modern world and holding a coding workshop, where he taught them how to write a small computer science program.

“I basically answer one question, what is an algorithm?” Che says. “At the end of that day, most of the kids know what an algorithm is, but we go into a little more depth, talking about why we need algorithms to save time and money for our work.”

In the subsequent days of the elective, the other graduate students went more in depth into the pros and cons of the various algorithms. Maynard, who handled the third day of each session, focused on the behind-the-scenes mechanics of TikTok, a subject she and the high-schoolers were excited to discuss. They talked about the methods the short-form video app uses to tailor content to its users’ interests as well as some of the data privacy concerns about the software.

“We talked about how the algorithms are made and what information they collect about you to make their algorithms work,” Maynard says. “We talked about the cool sides of technology, but also the ethical questions about it.”

Face recognition controversial

On the second day of the program, Fluellen tackled an even more controversial subject: facial recognition. The software uses artificial intelligence to match a person’s face from an image against a database of faces. While the technology can come in handy when identifying people in an assortment of photographs on one’s phone or unlocking a mobile device easily, it has come under fire for its potential to violate individuals’ civil rights. 

It has also frequently proven to be inaccurate, particularly with people of color, and various chapters of the American Civil Liberties Union have sought to have it banned from being used by law enforcement.

As part of her lesson, Fluellen talked with her students about the benefits and harms of facial recognition, because, she notes, “the general idea of the Power of Algorithms is looking at the way algorithms play into our daily lives.”

“One pro we focused on is how facial recognition makes our lives easier, allowing us to login to phones and apps quicker,” Fluellen says. “We also talked about how it can be inaccurate, especially with people of color, and can be harmful.”

At the end of each day, the SMASH scholars were left with looming questions about how to ethically create algorithms so the technology’s benefits far outweigh its harms. Continuing this theme, on the last day of each session, Dhaundiyal introduced the high-schoolers to the topic of cybersecurity and discussed how algorithms can potentially become destructive tools if not designed correctly.

Students talk in depth

Since the young scholars grew up with this technology, they could talk in depth about the topics she brought up, Dhaundiyal explains.

“I asked them: To whom is this technology particularly helpful and harmful? Then I went into ransomware and malware attacks and why we need to protect data,” she says. “The students were really intrigued, and they had so many innovative and creative answers we didn’t think of.”

The four-person team’s far-reaching set of lessons can be credited in part to the fact that none of them have an official background in computer science, according to Dhaundiyal. They are in the Align Master of Science in Computer Science course of study, a program that allows students with undergraduate degrees in non-technical fields to obtain graduate degrees in computer science. Che’s expertise is in economics, Fluellen’s is in cognitive science and linguistics and Maynard’s is in chemistry.

Dhaundiyal, whose previous education and work was in dental surgery, notes the group’s diverse array of interests helped elevate their SMASH course, letting them bring varying opinions and areas of knowledge to their lessons.

“The fact that we had such different backgrounds allowed us to bring in different perspectives, which was really powerful,” Dhaundiyal says. “That was really insightful even for me, as a person who was teaching.”

Connecting with high school students

Like the SMASH scholars they taught, the Align students are also still learning about computer science, as the four of them recently completed the first year of their master’s program at Northeastern, Che points out. However, their newly learned knowledge of computer science has also allowed them to connect easier to the high-schoolers, some of whom “are like hackers” and others who are still at the beginning of their computer science education, he notes.

“We just learned CS for two semesters, so we’re totally in these students’ shoes,” Che says. “That’s our advantage.”

Although the group is at the start of their master’s program, both Dhaundiyal and Maynard have taught entry-level computer science lessons to young students in the past, Dhaundiyal in India and Maynard in Philadelphia. These experiences helped prepare them for the SMASH program and allowed them to empathize with the young scholars when they came across obstacles in their coding.

“That’s where I developed my love for computer science and started thinking about Align,” Maynard says about her previous teaching experience. “I knew that I would be able to take topics that I recently learned and relate them to students younger than myself.”

“It was easier for me to relate and understand those little hurdles that the students encountered,” Dhaundiyal adds about her background. “This program was made not to frustrate them, but to make them fall in love with CS.”

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