About half of all adults in Brazil did not finish high school. And nearly one-in-five fails to finish elementary school. But an engineer in Rio de Janeiro is trying to make a difference - by bringing the classroom to the streets. CGTN's Lucrecia Franco reports from Rio.

In March, Silverio Moron, a 63-year-old engineer decided to help needy students in Rio de Janeiro. He walks a couple of blocks with a bundle of textbooks through the streets of Botafogo, a beachfront neighborhood in Rio. At a small and colorful square, he sits at one of the concrete tables with a sign that reads, "I solve doubts in Mathematics and Physics - Free." From 11 to 2 every weekday, he offers classes to a growing number of students who have turned 25.

SILVERIO MORON ENGINEER & VOLUNTEER TEACHER "Until the end of the year, mid-December when the school period ends, I aim to have 270 students."

His first engineering student was Marcio Almeida, who had stopped studying and couldn't keep up with his classmates.

MARCIO ALMEIDA MORON'S STUDENT "It was thanks to him, I call him my master, that I didn't quit. When I saw that blessing sign saying it was free and met him, I changed my mind."

Moron is not a trained teacher, but he's been giving private classes for almost 14 years and now has bigger dreams.

SILVERIO MORON ENGINEER & VOLUNTEER TEACHER "If I am able to raise the education level, I will be able to invert a situation that affects all of us and that is violence."

His success has encouraged others to join him including a 75-year-old retired computer analyst.

DULEME ALEIXO COMPUTER ANALYST "His initiative is something that needs to be followed, so I have decided to join him."

Moron's success began after a passer-by took a photograph of him with the free classes sign. In just one day, it was shared by more than 40,000 people on social media. The engineer who loves teaching and numbers says he uses an equation to explain what he does.

SILVERIO MORON ENGINEER & VOLUNTEER TEACHER "Education plus time plus unity is equal to less violence and more jobs that's called citizenship."

Moron says educating Brazilians is no longer just a dream but a question of helping others with whatever time and knowledge he has. Lucrecia Franco, CGTN, Rio de Janeiro.