Secondary school mathematics consists of mathematics typically taught in middle schools (a.k.a., junior high schools) and high schools (or secondary schools) — that is, roughly ages 11–17. It is preceded by primary school mathematics and followed by university level mathematics.
Note that the usage of the term secondary education is not consistent around the world, but it is convenient to separate the mathematics typically studied before adolescence from that studied during and after this period, since the latter is generally of a qualitatively different nature (i.e., more abstract). University mathematics, on the other hand, typically has a breadth (and depth) lacking in the high school curriculum, and so deserves its own classification.
Major areas of mathematics studied at the secondary level include: