Maths in english

Math tv (videos by tópic)

Second degreebequations. :  http://www.departamentos.ieshernanperezdelpulgar.eu/index.php?option=com_content&view=article&id=303:cuadratic-equations-activity-3o-eso&catid=87:d-matematicas&Itemid

http://m.youtube.com/watch?v=CQpy2gwGUuA


http://www.mathplayground.com/mathvideos.html