I started leaning how to teach mathematics at Hasenschule (http://www.hasenschule.de/). I attend twice to four times a week, one hour lesson each. This is a voluntary activity and I don't get any money. (Well, sometimes I got sweets or a piece of cake.) I would like to write about this activity.
Briefly speaking, Hasenschule is a special school for children who could not catch up with their school. This school teach how to read, write, and calculate. I am interested in teaching math and physics to children and want to learn how to teach that. With help with my friends, I found the following web pages. Gute-tat is a kind of portal organization, they introduced me Hasenschule. There are many activity of this kind in Berlin, if you are interested in, these pages are good start. My lessen is taught in German, but my German is not well. Hasenschule provides a rechtschreiben (reading/writing) course for 8-10 years old children, I maybe should take the course.