Photographs can be a brilliant way of just starting a conversation or can be used to structure a whole lesson around. As long as you choose the correct activity they can be used by learners of any level.
A picture could be used simply to state what is seen and build vocabulary. This could be extended to discuss how the picture makes you feel. You could speculate about what is happening in the picture, before building in the past and future tense by asking what might have happened before the picture was taken and what might happen next.
You can share photos of places you like and things you enjoy and ask your learner to do the same. They can be a great way of removing barriers and making learners feel at ease. You could even set work outside of lessons for the learner to take a picture of what interests them then talk about it in the next session.
Below are a number of sites that have some great photos and some ideas for how to use them in a session. Enjoy, and be creative!