PORTLAND — Casco Bay High School enrollment will grow next year as a part of a three-year expansion project to meet increasing demand.

The high school is now capped at 70 students per grade level because of space limitations. But with the expansion, ninth- and 10thgrade class sizes will increase by 30 students.

The additional students will cut the waiting list in half for first-year students; all sophomores currently on the waiting list will be accepted.

In addition to the expansion planned for the 2013-2014 school year, the school is planning to continue to accept more students until it reaches enrollment of 400 students.