The security gate swung open, along with a classroom door.

"There is a sign on my classroom door that says everyone smiles in the same language."

After all, they could very well feel that their responsibilities toward the students ended at the classroom door.

The Curse started when "21" was found written above the classroom door.

It can never be enough to close the classroom door and teach well.

When the painting was finished, the teacher hung it on the classroom door.

He had to lower his head to get through the classroom door.

She put on her jacket, walked to the classroom door, then remembered something.

I walked off down the hall, having to pass by his open classroom door.

I asked her as she paused and nodded before another classroom door.