This site has some amazing links for all the content areas: sciences, lanugage arts (lit trips), maths, and social studies, including U.S. History Tours, using Google Maps and Google Earth. For multiple grades.
Captions are the law, but also they may aid ESL students and students with learning disabilities. Some evidence is provided for improvement in test scores, and captioning certainly is a study aid. Captions can also aid in video searches.
It's the law, but captioning also helps ESL students and students with disabilities. There is also some evidence of improved test scores when captioning is used throughout a school term. Captioning also makes video search easier. T/h to N. Flynn (cielo24.com)