SOUTH PORTLAND — Starting this year and for many years to come, every student who graduates from South Portland High School will receive a $1,000 cash award thanks to a $4 million gift honoring the Class of 1948.

The school board is set to formally accept the gift Monday from a donor who has asked to remain anonymous, Superintendent Tim Matheney said.

The money will be used to establish an endowment fund to provide cash incentives for students to graduate. The fund’s investment structure is expected to keep it viable far into the future.

About 240 students are expected to graduate from South Portland High in June. They will be able to use the money however they choose, Matheney said.