senior public school Senior Public School, senior Public School DCHP-2 (October 2016)
n. — Ontario, Education
a public school for students in grades 6-8 or 7-8.
Type: 5. Frequency — The term senior public school is currently used in Ontario to refer to a public elementary school for students in grades 6-8 or 7-8. The term's frequency in Canada is largely due to its presence in Ontario (see Charts 1 and 2). While the Canadian education system uses the general umbrella of elementary and secondary education to refer to public education for students generally aged 6-16 (see CMEC reference), education is under provincial jurisdiction (see CICIC reference), which explains why this term is so infrequent in other provinces and territories.
See also: junior public school
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Chart 1: Internet Domain Search, 3 Apr. 2014 
Chart 2: Regional Domain Search, 2 Apr. 2014