The Google Cultural Institute offers museum resources from around the world. The Hiroshima Peace Museum exhibits are available here:
http://www.google.com/culturalinstitute/collection/hiroshima-peace-memorial-museum?projectId=historic-moments The materials include a focus on lost neighborhoods and last words (diary entries and more). There are many photos. As is always the case, teachers need to be sensitive about what they share from this site and how they do it.
There are also videos and other materials from the Nagasaki Atom Bomb Museum.
http://www.google.com/culturalinstitute/collection/nagasaki-atomic-bomb-museum?projectId=historic-moments
The Life Magazine photo collection includes materials from both bombings.
http://www.google.com/culturalinstitute/browse/nagasaki?q.8129907598665562501=1000&q.openId=8129907598665562501&projectId=historic-moments
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