École secondaire catholique l'Essor is a publicly funded separate (Catholic), French-language high school located in Tecumseh, Ontario, Canada (formerly St. Clair Beach), established in 1979. It serves the Francophone population of Essex County. The name l'Essor, coined by local resident Florence Limoges, is a portmanteau combining "Essex" and "Windsor". Essor also refers to the French word "to take flight". The school belongs to the Conseil scolaire catholique Providence.

The small school participates in a wide variety of local activities in the Francophone community. A notable example is the Franco Bowl, an annual football match against neighboring Windsor's French Catholic high-school, École secondaire E.J. Lajeunesse. The school has a very high percentage of graduates and high test scores.^{[citation needed]}

• Brian Bulcke, football player, played in the CFL with Hamilton Tiger-Cats and Toronto Argonauts
• Andrew Dowie, former town councilor for Tecumseh and current MPP for Windsor-Tecumseh
• Taras Natyshak, MPP for Essex
• David Tremblay, 5 time CIS National Champion, 2014 Commonwealth Gold, 2012 Olympian – Wrestling
• Paul Vallée, technology entrepreneur and CIGI Senior Fellow
• Kyle Wellwood, retired NHL hockey player

Sports include: Football, Hockey, Basketball, Soccer, Volleyball, Wrestling, Golf, Tennis, Badminton, Swimming, Softball, Baseball, Cross Country, Track and Field

• List of high schools in Windsor and Essex County, Ontario
• List of high schools in Ontario