WASHINGTON — It’s been a year, but the air is still frigid between the education secretary, Betsy DeVos, and the leaders of the nation’s teacher unions.

Randi Weingarten, the longtime president of the American Federation of Teachers, and Lily Eskelsen García, the president of the National Education Association, were left out in the cold on Thursday as they tried to deliver 80,000 failing “report cards” to Ms. DeVos from educators across the country.

The union leaders found locked doors as they tried to enter the Department of Education building to offer their assessment of Ms. DeVos’s first year on the job.

Ms. Weingarten said the department had been asked for an appointment and knew that the group of about 100 protesters was coming. The department said guards had barred the group because it did not have an appointment.