(CNN) Chicago public school students in grades kindergarten through 5 who chose in-person learning were able to return to classrooms Monday.
Mayor Lori Lightfoot visited Hawthorne Scholastic Academy to welcome students back after almost a year of remote learning.
"This morning I was lucky enough -- once again -- to experience firsthand the infectious excitement of our young people on their first day in class," Lightfoot said.
"Driving here this morning, I saw young kids skipping ahead of their parents with excitement about coming back to school."
As part of an agreement with the Chicago Teachers Union earlier this year, children in pre-kindergarten and cluster programs were able to return to in-person learning February 11.
Students in grades 6 through 8 are expected to be able to return next Monday, March 8.
Grades 9 through 12 will continue with remote learning. No date has been set for when they will return to classrooms.
Janice Jackson, chief executive officer of Chicago Public Schools, said seeing children back on campus "warms my heart."
She said hearing the students' "joyous laughter" is "just something that reminds us of why this was so important."
The mayor noted that "trauma amongst our young people is real. Depression, feeling of isolation, is real."
"We can't truly recover as a city if we're not thinking about the stress and the burden that has been on our young people," Lightfoot said. "And we need more conversations about that particular issue."
Jackson said several schools are "experiencing challenges" with teacher staffing but there are no schools that can't reopen because of staffing.
"We have deployed hundreds of individuals from the central office out to these schools," she said. "They will be there until we can ensure that there is a replacement, and make sure that the situation is stabilized."