España 
Italia 
United States 
Brasil 
Chile
Ecuador
Mexico
Colombia
Perú
Tell us about your work, Cecilia:
I am a mathematics teacher and a teacher of teachers. I started teaching in 1989 and since then, I have never gone more than a year without setting foot in a classroom. It is my natural place.
How do you remember your experience as a mathematics student?
Until high school, I didn’t think much about them. Math was not hard for me, but I didn’t feel any special passion for it either. Everything changed the day I failed my first geometry exam: From that setback onward, I started paying more attention to what I was doing while learning mathematics. That experience was key: I discovered that you can enjoy math through its challenges.
You studied in Uruguay. What do you remember?
I earned my degree in Mathematics at the University of the Republic and trained as a secondary teacher at the Artigas Teachers Institute (IPA), which was heavily inspired by the French model. That is where I discovered my passion for math education, thanks to professors who were already connected to Europe and familiar with new research trends. It was eight years of training in total.
How did you end up in Catalonia?
When I finished my studies, I wanted to continue connecting mathematics with education, but at the time there were no graduate programs in Latin America. I wrote to several European universities, and the University Autonomus of Barcelona opened its doors to me. It was 1995. I remember walking into the library for the first time and seeing shelves full of education journals. Today, Uruguay has a strong community dedicated to mathematics education, but that wasn’t the case in the 90s, so that UAB library felt like a treasure. Thirty years later, I’m still here.
What did research teach you?
That you can do very advanced mathematics with elementary knowledge. During my dissertation, I realized that mathematical thinking doesn’t depend on the level of content, but on the depth with which you work on it. This idea is the foundation of the rich tasks I have always advocated for: activities that allow you to think like a mathematician starting from basic concepts.
Have you had important mentors or role models?
Yes, and some of them weren’t even my professors, but colleagues. I would highlight two teachers: Viva Gilb, for her passion and rigor, and Elda Rodriguez, who taught me the importance of planning and keeping the board neat and organized. There was also a professor who marked me by contrast: he taught only for the 10% who understood him. He made me see how I didn’t want to teach. I want to speak to everyone, respecting diverse styles, rhythms, and interests.
What does “doing mathematics” mean to you?
Doing mathematics means facing situations you don’t know how to solve. It is not about imitating or repeating; it is about thinking, connecting, reasoning. When a student learns to use their tools to move forward in a new situation, that’s doing mathematics.
And can everyone do mathematics?
Of course they can! The goal is not for everyone to be a mathematician, but for everyone to read the world through mathematical eyes. For everyone to understand reasoning, value deduction, and make informed decisions. This is not taught in 10th grade, it starts in preschool: a culture of mathematical thinking that accompanies students throughout their education and allows them to choose their path freely.
What myths still weigh on mathematics?
Many. One of the most deeply rooted is believing that students learn by watching the teacher. But math is not a spectator sport: you have to get on the field and play.
In society, an old image still lingers: students in rows, the teacher at the board solving problems, and students repeating procedures and memorizing for the exam. We need to transform this image if we want math to be a living experience in the classroom.
Do manipulatives play an important role in this “living experience”?
Here is another myth: that hands-on materials are only for little kids. Not true. They are fundamental even in high school. I remember workshops by UB’s Cubic group where entire rooms were filled with teachers working with materials to understand advanced concepts. If you know how to use them, the same material can have many lives in the classroom: a tangram can serve to discover geometric shapes and fractions at different times in elementary school and later to be used to discuss irrational numbers in middle school. It is not the material that matters, but the life we give it; the questions we ask around it.
Do you think virtual materials are replacing physical materials in classrooms?
Physical and virtual materials make a perfect pair: manipulatives let you experiment, touch, build; virtual tools make communication and shared reflection easier. And if there aren’t enough physical materials, a virtual simulator can complement them. When one supports the other, learning is much deeper.
So, what does your ideal mathematics classroom look like?
With students eager to think and teachers who convey passion. A living, flexible classroom where students work in groups, move chairs, exchange ideas, ask questions. With rich tasks, diverse materials, and technology serving thought. But the most important thing is not the space or the resources; it is the classroom culture: students feeling that coming to math class means coming to think.
What advice would you give a young teacher?
Never stop learning or showing passion. Students need to see that you learn too; that you read, make mistakes and explain them, bring new ideas. We are role models: if we want curious students, we need to be curious teachers. If we want them eager to learn, they need to see us learning.
And to teachers who have lost some motivation?
I would tell them to find energy in the community. Watch a talk by Anton Aubanell, Núria Serra, Carles Granell, or Sílvia Margelí. Enthusiasm is contagious. Mathematics teacher associations are fantastic spaces to recharge and feel you’re not alone. There is always someone ready to inspire you to return to the classroom with renewed enthusiasm.
What has been the class of your life?
I hope it’s tomorrow’s. I always leave class thinking I could have done something better. But looking back, I especially remember a session on the greatest common factor we did just before lockdown. Students discovered it by subtracting, not dividing, using both manipulatives and virtual materials. When a student says “Ah, now I get it!”… That moment is worth more than any published article.
