Nobody gives anything to teachers for free and they are highly promoting this site saying it is supported by a physicist, but not giving his name and some of the content in the videos seem a bit veiled. Maybe I am leery in that there are lots of people with agendas trying to push their thoughts on science teachers lately. I need to know more information. And no, the fact that they are from the south is not the reason I am concerned. I am just seeing folks with big money from corporations with agendas trying to push their ideas onto science teachers. In West Virginia it is coal companies offering to send free materials on mountain top removal and seeing stuff from them written into suggested curriculum guides. Stuff like that.