David G.

I was a high school Chemistry and Physics teacher for years, now I teach teachers. I've lived in Australia, Papua New Guinea and Canada and worked in South Africa.


3,753,592 students helped

Level 17 in Physics Level 14 in Chemistry Level 13 in Algebra Level 9 in Precalculus Level 6 in Geometry Level 5 in Trigonometry Level 2 in Socratic Meta