STRING SECTION: Students at Grace A. Dunn Middle School in Trenton are learning the violin from José Gregorio Sanchez Rodriguez, who is a product of the highly successful El Sistema program in Venezuela. Rodriguez also teaches at Westminster Conservatory in Princeton.

In a cluttered classroom at Trenton’s Grace A. Dunn Middle School, seven girls and one boy stand in a circle, violins in hand. It has been barely a month since they began learning the basics of the instrument. But “Twinkle Twinkle Little Star,” which they are playing along with their teacher, is sounding pretty good.

The students are urged on by José Gregorio Sanchez Rodriguez, who issues gentle but firm commands from the middle of the circle. In quick succession, they try out different rhythms of the familiar tune.

“Vamos! [‘Come on’ in Spanish],” he says (Dunn is a bilingual school). “We have to set up the hand first so the fingers know where they belong. We have to be ready!” It is the end of a school day, but the students, who have been assigned the instruments for the school year, keep up the quick pace of the drill. Mr. Rodriguez’s enthusiasm is clearly contagious.

Getting kids fired up about music is a goal of Trenton Music Makers, a collaboration between the Trenton Community Music School and the Trenton Public Schools. The program began last year with 45 children at the Grant Elementary School. This year, 70 are taking part. Dunn, where 24 students are studying violin, viola, cello, and drumming, was added this fall.

The program follows the lead of El Sistema, a highly successful music education program for underserved children, founded in Venezuela 41 years ago. Of the eight instructors on the Trenton teaching team, Mr. Rodriguez is perhaps the most uniquely qualified. The 53-year-old native of Venezuela is a product of El Sistema, which he credits with altering the direction of his life.

“If not for that program, I could never have been able to do what I do today,” he said. “My life changed completely. I believe in the power of music because I have experienced it myself.”

Mr. Rodriguez was eight months old when his very young mother left him with her parents. His grandparents raised him in a little village called Cubiro. “I was a very sick child,” he recalled. “When I was about five, I was left in the hospital. I started to sing. I discovered I could make a little money because the nurses would pay me. After I started school a year or so later, my grandfather gave me a cuatro, a four-string guitar. From then on, I accompanied myself.”

The little boy became a folk musician, singing on weekends at the restaurant where his grandmother worked. “People called me ‘El Cantante’ in the village. I would wear my only suit,” he said. “Later on, I played and sang in school. I was also on the radio.”

When he was 14, Mr. Rodriguez took part in a choir festival at school. The conductor of another choir at the event noticed his talent and sent him a note, asking him to get in touch. “I called him from the only phone in town,” Mr. Rodriguez said. “He asked me if I would be interested in studying music in Quibar, where they were starting one of the El Sistema programs. So that was my introduction to studying music.”

The teenager, whose grandfather had died four years earlier, ended up moving in with a family in Quibar. He was introduced to Jose Anotnio Abreu, the founder of El Sistema. “He was impressed by the fact that I was an orphan kid,” Mr. Rodriguez said. “He asked me what instrument I’d like to play, and I said violin. I got a scholarship and started traveling to Caracas to study there. Then, everything started happening so rapidly.”

By 18, Mr. Rodriguez was a member of El Sistema’s Simon Bolivar Orchestra. He began traveling with the acclaimed group, performing in concert halls across the globe. “In three years, I went from living in a little village to playing with this famous orchestra,” he said. “It was the first time I encountered direction. The whole experience changed me; it opened my mind.”

Mr. Rodriguez decided to apply to The Juilliard School in Manhattan, and was accepted. It was while studying there that he took his first course in the Suzuki method, which aims to create an environment for learning music which parallels the linguistic environment of acquiring a native language. He was immediately captivated.

“I had always liked teaching. And I was fascinated by how little kids would learn to play an instrument,” Mr. Rodriguez said. “I started using the method and thinking of ways to combine it with what I learned at El Sistema. I identify with it very much because of my own experience as a child, making music without knowing how to read music. It’s about ear development, and I believe in this approach. I have applied it to my own way of teaching.”

Mr. Rodriguez earned undergraduate and graduate degrees at Juilliard. He spent time playing with an orchestra in Mexico, where he also started a chlldren’s orchestra, before moving back to the United States to teach with the El Sistema-inspired Play on Philly program in Philadelphia. He stayed for three years.

He moved to Trenton in August. Mr. Rodriguez is teaching at Princeton’s Westminster Conservatory of Music as well as the Grant and Dunn schools. While he is enthusiastic about Trenton Music Makers, he hopes to see more parents get involved.

“We need to educate parents and get them engaged,” he said. “More people should know the benefits of studying music. The evidence is out there. It makes a difference in children’s lives.”