Photography can be classified as a type of picture in the teaching process. What is the difference between a usual drawing in the textbook or on the blackboard and the photo? The picture is understood as a simplified reality, it could be accepted differently from the pupils´ view because it includes more information or presents history or future (for example sci-fi), traditional or authors´ fantasy (fairytales, mythology ...).
Generally, using of drawing/picture is a part of didactical contract.