Westlake Academy — the state's only municipal charter school, celebrating its 10th anniversary this year — started a major expansion this month.

Groundbreaking for the additions, which will cost roughly $85 million, was June 6 at the school.

Westlake Academy started with 195 students, and is expected to grow to 1,300 in the next 20 years. In fall 2012, 650 were enrolled.

This year's 41 graduates received more than $3.8 million in scholarships and grants.

The appeal of the school, which uses the holistic-style International Baccalaureate curriculum, is credited with drawing more residents to Westlake, as are real estate prices lowered by the recession.

Westlake residents are automatically admitted. Remaining spaces are filled by an annual public lottery, which generates a long waiting list each year.

The work will include a three-story secondary classroom building, a multipurpose building and an athletic field house.

More expansion is planned in 2019 and 2025.