# Resources for high school teachers about APOS theory

As far as I can find, the major resources available to the layteacher about APOS (Action, Process, Object, Schema) theory refer to "undergraduate" concepts such as group theory and vector spaces (such as here).

I am interested in whether people have implemented or investigated APOS theory at the high school or lower-undergraduate level, and whether there are resources for the high school math teacher that can be used concretely, for example, to design a unit. So far I have found this book, but this seems unnecessarily technical to reach a larger audience of teachers.

For example, when I described APOS theory to my coworkers, they immediately connected to it and it helped them understand the struggles that their students were facing in particular problems, such as transitioning from seeing "sine and cosine" as "find the ratio between pairs of sides" to "functions." However I was unable to find good reading for them that referenced mathematics that they used frequently.

• There are certainly individual papers using APOS theory at the pre-college level. For example, you mention functions and there is the paper High school students' understanding of the function concept (pdf) by Dubinksy and Wilson (JMB, 2013). As to resources for high school math teachers: not of which I am aware; good question, +1. – Benjamin Dickman Aug 23 '17 at 20:52