DIXFIELD — Dirigo Middle School eighth-graders on Monday packed up 750,000 pop-tops which represent about half the number of youths killed in the Holocaust.

The project started four years ago as part of a collaboration among teachers in different subject areas.

On Monday, students packed up more than two dozen boxes, at least a dozen bags, and several large plastic jars filled with the aluminum tabs. They were brought in by students, school employees, parents and other community members.

“Every day I’d come into school, I’d find some in my mail box,” math teacher Sarah Irish said.

On Wednesday, Shriners will pick up the pop-tops for recycling with the proceeds going to children in need of medical care.

Irish said about 15,000 pop-tops will stay at the school to represent the number of children who lived in the Terezin ghetto in Czechoslovakia during World War II. About 150 of those pop-tops are colored and represent the number of children who survived that ghetto.

Eighth-grader Sela Smith said the project was emotionally intense.

Eighth-grader Celine Bolduc said she couldn’t believe how many people were killed in the Holocaust.

Both girls were fifth-graders when the project began.

Irish said she’ll encourage her students to continue saving pop-tops.