Phone: (925) 473-2390 x 7750


Degrees and Certifications:

Mr. Kleinjans

Hi. My name is Mr. Kleinjans. I've been teaching for more than 30 years; for the last 15 years, I've been teaching math at PHS, where I have taught Algebra 1 Support, Algebra 1, Geometry, Algebra 2, Precalculus, Statistics, and AP Statistics. 

This says Biography, so, OK: I was born in Japan in 1951. My parents were educators. We moved to Hawaii in 1967, where I went to the same high school as Barack Obama (later). I took 10 years to learn how to live in America and earn my bachelor's degree (in Natural Sciences); then I joined the Peace Corps and spent three years in the Congo, where I taught high school (in French), learned two African languages, and supported other volunteers. I returned to Hawaii and earned a master's degree in Tropical Agriculture. I spent a little time working in computer support in Western Samoa, Guam, Saipan, Pohnpei, and American Samoa. In 1992 I moved to Mississippi with my wife, who taught psychology at Jackson State University. We moved to the Bay Area in 2000. 

My philosophy of education is: we have Conversations about Ideas.

And then try some things we haven't done before, and almost certainly make some mistakes. That's OK. Just learn from the mistakes, so we don't keep making the same mistakes over and over again. Get some right, then get some more right. And eventually figure it out.

The only time that you don't make mistakes is when you're doing something you already know very well -- and if you're doing that, you aren't learning anything new. Remember: every time you learn anything new, you will make mistakes. If you aren't making mistakes, you aren't learning. So in many ways, making mistakes is a Good Thing. Get comfortable making mistakes, and learning from them. Have patience. Keep trying.

Right now, I'm trying to figure out how to make good things happen in this new environment. We're all learning here. Many things, including this site, will change often. We'll all be trying to make things work, and we'll all be trying new things, making mistakes, getting some things right,and learning from the experience. Let's just all keep trying to make things work as well as possible ... and try again to make things even better tomorrow. And try to not keep making the same mistakes over and over again. 



  • Hi. I'm Mr. Kleinjans. 


    This is Geometry with Mr. Kleinjans. My Google classroom code is 3thfxnt. 

    I'm figuring this out myself.