A man writes on a whiteboard as he teaches a class.
Man in a black shirt writing an equation on a board with people in chairs watching him.
Man standing in the front of a classroom writing math equations on a white board.
A man is teaching a class while writing on a white board.
Male teacher stands in front of classroom and writes on whiteboard with head turned to side.
A man standing in front of a class was writing on the board
A man is teaching a math class by explaining a formula on a white board.
A male teacher is in the front of the class doing a mathematical problem while students shout out.
A man is teaching math and writing on a dry erase board at the front of a classroom.
A man stands at a whiteboard and writes numbers while students watch.