An idea.
i am a math teacher at high school. i am 35 years old. Maybe i have started learning English late, but I am trying to improve myself.
Americans say 'math', British and other English speakers say 'maths'. 'Mathematics' is also correct, but it is usually only used in formal situations.
An idea
I am a high school teacher and I am teaching Mathematics. I am 35 years old. I have started to learn English very late but I am trying to improve it.