I am a native German speaker.
I supported a Persian girl that came new to our school and had difficulties with the German language. I helped her improve her language her pronunciation and with the topics in the lessons for 2 years.

I played the piano for over 11 years and before 2 years I started teaching the little brother of my best friend playing the piano one time per week.

I teaches mathematics several students from my school for 4 years. I did this most of the time 1-2 times a week.

I played volleyball myself for 7 years and trained the youth team of my club for 1,5 years twice a week.

Most of the students I teached mathematics also needed help in Latin, so i splitted the time up.

Algebra is a part of the mathematics I teached the children. At least 3 had algebra as their current subject in school.