Spanish and English tutor providing classes to children of different ages

Even though I am an industrial engineer and I have work experience in the industry, when I was in Mexico and South Korea, I used to teach Spanish (my mother tongue) and English to children. Also, when I was in Bolivia, I used to teach mathematics, physics, and chemistry to 3 girls who were 7, 9, and 15 years old.
In addition, when I was in Mexico, I worked as a teacher of 7 to 12 years old children teaching values in a church and in South Korea I used to teach Spanish to korean children.