n. — Ontario, Education
in Ontario, an elementary school in the public school system for pupils from junior kindergarten to grade 5 or 6.
Type: 5. Frequency — The term junior public school is an Ontario term of long standing (see the 1893 quotation) and is used to refer to a public elementary school that does not go beyond grade 6. Boberg (2005: 40) notes that public school is the Eastern Ontario term for elementary school. The term's dominant position in Canada (see Chart 1) is owed to its status as an Ontarianism (see Chart 2). While the umbrella term elementary education is used to refer to public education up to secondary or high school in Canada (see CMEC reference), provincial jurisdiction over education explains the use of regionalisms in that domain.
See also: senior public school
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Chart 1: Internet Domain Search, 2 Apr. 2014 
Chart 2: Regional Domain Search, 2 Apr. 2014