The Department of Defense has agreed to change the database it uses for military recruitment efforts to better protect the privacy of millions of high school students nationwide, a civil liberties group announced yesterday.

In settling a lawsuit brought last year by the New York Civil Liberties Union, the government agreed it will no longer disseminate student information to law enforcement, intelligence, and other agencies and will stop collecting student Social Security numbers, the group said in a statement.

It said it will also limit to three years the time it retains student information and will clarify procedures by which students can block the military from entering information about them in its database.

The government published the changes in the Federal Register yesterday before they were announced by the NYCLU.

A spokeswoman for government lawyers who worked on the case, Yusill Scribner, said the government had no comment.

Even with the changes, Congress will need to be vigilant about how the military recruits students, NYCLU Executive Director Donna Lieberman said.

“This lawsuit was designed to protect the privacy rights of American high school students who are subject to data mining by the military as well as recruiters in their schools,” she said. “With this lawsuit, we’ve increased the protections for them and limited the type and amount of information that the military can gather and what it can do with the information.”

She said the NYCLU wanted students to know that they need to notify the Defense Department that they don’t want to be in the database and tell their high schools not to provide the military with their contact information.

The NYCLU had challenged the government recruiting practices in a lawsuit on behalf of six high school students, who did not know if they were included in the database. It said the department was disregarding privacy boundaries set by Congress for the collection, maintenance and distribution of students’ personal information.