As a child growing up in the 70s I spent many a Saturday morning being unknowing educated on science concepts and American History by the geniuses of Schoolhouse Rock. While these are definitely not a new resource, I think that elementary school students will still find them to be engaging (at least they did a few years ago when I was in the classroom).
The songs and videos are available for purchase (click HERE for Barnes & Noble link) but they are also available on YouTube for free. The Schoolhouse Rock site also has lyrics to all of the songs.
See one of my Schoolhouse Rock Science favorites, Interplanet Janet, embedded below.
If YouTube is blocked in your school, try Kideos.
Science for All 