Langstaff Secondary School (LSS) is a public high school in Richmond Hill, Ontario, Canada.

Langstaff Secondary School is one of six schools in the York District to offer a French Immersion curriculum. Upon successful completion of the requisite French Immersion courses, students are eligible to receive a French Immersion Certificate.

Langstaff Secondary School offers the Advanced Placement programme to its students. The school offers AP courses in Chemistry, English, French and Math (Advanced functions, Calculus and Vectors). Like other AP programmes, students who complete the Grade 12 AP courses are eligible to write the AP exam.

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• Education in Ontario
• List of secondary schools in Ontario

• Official web site of Langstaff Secondary School