Time needed: 1 to 20 min.
Why? Sometimes it is hard to show a real object to your students. Especially if it is something like the Eiffel tower of Paris or a Bengali Tiger. Photos are an option if you want to show how something looks like.
When? Show photos when you want your students to visualize how something looks like.
How? The bigger the better if you show photos standing at the front. This means: DIN A4 (standard office paper size) the minimum, or use a beamer if available. You can nwLk through the isles or you can let students pass small photos through if there is anough time.
Any risks? Too small photos shown from the front, too less time if you pass them through, to bad quality could also be a drawback and always bear in mind: a photo is reality minus 1 dimension – they are flat, they don’t smell as the object they show and there is no time passing at the photo. Try to use 3D photos instead if you want try somethng out – this gives at least the third dimension back.