Secondary education, or secondary school, is a period of education which follows directly after primary education (such as intermediate school or elementary school), and which may be followed by tertiary or "post-secondary" education. The purpose of a secondary education can be to prepare for either higher education or vocational training. The exact boundary between primary and secondary education varies from country to country and even within them, but is generally around the seventh to the tenth year of education, with middle school covering any gaps. Secondary education occurs mainly during the teenage years. Primary and secondary education together are sometimes (in particular, in Canada and the United States) referred to as "K-12" education, (K is for kindergarten, 12 is for twelfth grade).
- Australia, United States: high school
- Austria, Germany, Slovenia, Sweden: gymnasium
- Brazil: Colégio
- China, Taiwan: zhong xue (中学; literally, middle school), consisting of chu zhong (初中; literally junior middle) from grades 7 to 9 and gao zhong (高中; literally high middle) from grades 10 to 12
- Canada: high school, secondary school, école secondaire, lycée
- France: lycée
- Hong Kong: Chung Hok (中學, Cantonese:ʤəʊŋ1 hɔk6, Secondary School
- Iceland: Menntaskóli.
- Indonesia: Sekolah Menengah Atas (SMA), Sekolah Menengah Pertama (SMP).
- Ireland: secondary school.
- Japan: chūgakkō (中学校; Lower Secondary School), kōtōgakkō (高等学校;Upper Secondary School), chūtōkyōikugakkō (中等教育学校; Comprehensive Secondary School)
- Netherlands: middle school
- New Zealand, United Kingdom, Singapore: secondary school or (where a middle school system is operated) high school
- Spain: Educación secundaria, ESO (Educación Secundaria Obligatoria)
- Turkey: Lise