Learning to teach, learning to discover

Nik Sandu points to a graph on the whiteboard in a seventh-grade science class. “According to the graph, what is the energy of the ball?” she asks, gently waving a hand to settle the room’s twitchy energy. “Voices are off.”

A student raises his hand, noticing an askew Y-axis. “This one doesn’t go through zero. A ball with no mass shouldn’t have any kinetic energy.” Sandu glances at the board, then back to the class. “Yes, that’s true — that was a little oversight on my part. No mass with no energy is a really good observation.”

The moment captures the MIT senior’s teaching style — reflective, open, and willing to learn alongside her students.

“The No. 1 most important thing in a teacher is being able to evaluate your own teaching, not take it personally, and fix things up as you go,” says Liza Huntington, Sandu’s mentor at the Community Charter School of Cambridge (CCSC). “Nik has that.”

That same openness and on-the-fly adaptability extend beyond the classroom. A materials science major working toward her teaching license through MIT’s Scheller Teacher Education Program (STEP), Sandu has taught high school in Norway, researched magnetoelectric materials and soil stabilization, worked in a Finnish mine extracting ferrochrome, and held leadership positions centered on community building. Each experience reflects a lifelong learner making an impact across roles and settings.

“You can see that in how she tackles different roles, whether it’s research or teaching or service,” says Professor Jeffrey Grossman, her advisor in the Department of Materials Science and Engineering (DMSE). “She’s multidimensional in all the right ways.”

Roots across borders

Born and raised in Chicago to Romanian immigrants, Sandu credits her parents for her commitment to education. They left Romania, where access to higher education was restrictive, so her mother could attend college in the United States.

“She got a bachelor’s in English, which wasn’t her first language,” Sandu says. Her mother later went into the workforce, but still aspires to earn a master’s degree. “Hearing her say, ‘I want to go back to school’ made me think: She’s successful.

She came here to America and got her education — and that motivation is a big part of why I’ve come to love education, both as a student and a teacher.”

With limited financial resources, Sandu’s parents strongly supported her intellectual pursuits. Music was a particular focus, a way to stay connected to Romanian culture. “So I know a lot of Romanian songs. When I go home, there’s Romanian music playing.”

By age 6, they encouraged her to take up guitar. She later performed in a youth folk band, the Young Stracke All-Stars, named for Chicago musician Win Stracke. The group played fundraisers and festivals, including an event at Wrigley Field, alongside folk music greats such as Arlo Guthrie and “First Lady of Children’s Music” Ella Jenkins. They also presented Jenkins with a lifetime achievement award and played a tribute concert for Pete Seeger.

Sandu laughs at her younger self’s perspective. “When you’re a kid, you’re like, ‘Oh, this is a cool musician.’ You don’t realize, ‘Oh my God, I met this person.’”

The road to MIT

Sandu became fascinated by STEM subjects at a selective-enrollment public high school in Chicago, taking advantage of every opportunity available, including advanced placement classes, college-credit courses, science fairs, and a class at a local community college.

But many experiences felt out of reach — elite courses and programs she was accepted into, but couldn’t afford. “My family wasn’t really in a position to drop $2,000 on a course or science equipment.”

A school like MIT seemed like a stretch.

She applied anyway on a whim and had the surprise of a lifetime when she saw her acceptance on her phone while in the car with her mom and sister — “I see the confetti and I’m like, ‘Oh my God, I got into MIT,’” she recalls.

She attributes her acceptance to breadth of experience and persistence, but especially to mentors — “teachers who knew how to push me, who knew how to support me, and wanted to see me grow as a student,” she says.

Their influence ultimately led her to the STEP program, which prepares students to become K-12 educators: “I was like, ‘I’m doing this for sure.’”

At CCSC, a tuition-free school that serves many sixth- to 12th-grade students from disadvantaged families, Sandu feels she has come full circle in the classroom.

“Seeing their opportunities and seeing them pushing themselves, and me wanting to be that person who also pushes them to be better students — that has just really affected my worldview,” she says.

A scientific lens

For Sandu, teaching is a way to share her love of science, from geology and the environment — as a first-year student, she wanted to be an Earth, atmospheric, and planetary sciences (EAPS) major — to materials science, while also recognizing how closely the fields connect.

After taking a few EAPS classes, “I was more interested in why these rocks behave the way they do on a chemical or a molecular level.”

That curiosity carried into her 2025 summer internship at Outokumpu Stainless, where she worked in a company-owned mine extracting ferrochrome, a chromium-iron stainless steel alloy. Her coursework helped her understand how the unusually deep, vertical mine formed over millions of years, and how minerals form.

“It was really cool that I had the background to understand that,” Sandu says.

Her research through MIT’s Undergraduate Research Opportunities Program (UROP) followed a similar path — starting with an EAPS study investigating how roots stabilize the soil. She helped choose materials for a 3D-printed root network model and developed a data-collecting procedure using a high-speed camera.

She applied that same problem-solving approach in later materials science research, studying magnetic waves called magnons in a garnet material, tracking how boundaries known as domain walls moved and could be steered in different directions — work with applications in energy-efficient electronics.

Miela Gross PhD ’25, her supervisor on the project, says Sandu’s methodical approach to research was an enormous help. She organized massive datasets, troubleshot equipment issues, and even mastered pulsed laser deposition — a technique for growing new thin films.

What stood out — beyond her research skills — was her facility with communication. Gross described her as clear, proactive, and collaborative; Sandu would raise issues as soon as they came up, rather than waiting to report them later, and she was deliberate about setting and negotiating deadlines depending on her classwork and availability.

“She was really good at asking the right questions: ‘OK, these edge cases that might come up, what should we do there?’” says Gross, now a postdoc at Helmholtz-Zentrum Berlin, a national lab in Germany. “Nik’s passion for science is clear, but her communication is what drives the impact of her work.”

Sense of community

For Sandu, education and community are inseparable. In addition to her research and teaching at CCSC, she has served as a teaching assistant in MIT physics classes, been social chair for DMSE’s Society for Undergraduate Materials Scientists, and helped coordinate the weeklong First-Year Pre-Orientation Program (FPOP) for incoming students, which included a scavenger hunt and an “Among Us”-themed murder mystery, complete with inflatable costumes.

“I prioritize community in all aspects of my life — social, academic, personal,” she says. “For FPOP, we wanted incoming students to know that there’s a community for them at DMSE.”

Gross saw Sandu’s generous spirit extending beyond MIT, noting how she tutored a family friend in high school physics. “She’s just very giving,” Gross says.

Rhea Vedro, lecturer at DMSE and metals artist-in-residence, taught Sandu in class 3.095 (Introduction to Metalsmithing), where students learn to solder and form metal objects. In addition to Sandu’s incredible drive — “if a minimum of five rivets was required, Nik would do 20” — Vedro highlighted a strong commitment to peers, pointing to leadership in the classroom.

“Nik would always do the very best, and that would set a tone for the rest of the group — to rise to that standard,” Vedro says.

Paths forward

Now in her final semester at MIT, Sandu is preparing to pursue a PhD at Dartmouth College, where she will combine materials science and geology to study cobalt minerals critical to lithium-ion batteries. The research builds on her earlier work on magnetism and mineral structure.

At the same time, she is completing the requirements for her Massachusetts and Illinois teaching licenses. It has been a difficult balance between the pull of research and teaching.

“I’m not quite done learning about the world. I’m not ready to leave the academic environment where I’m expected to keep learning,” she says. But teaching remains a long-term goal, especially in Chicago.

“I want to give back to that community that helped me grow, helped me become who I am today,” Sandu says.

Her advisor, Grossman, says Sandu stands out for how she thinks about her experiences and what she learns from them.

“Just hearing her reflect on her experiences — it’s very mature. And that’s a really important part of the experience and the growth that undergraduates do here,” Grossman says. “It’s taking a step back, thinking about what you’ve done, understanding it more deeply, and learning about yourself in the process. Those are the skills of lifelong learners, and she’s already showing them in spades.”