This link to the Oxford English Dictionary is an invaluable resource for Middle School ELA and Secondary Ed English teachers. I can see it as a frequent "go-to" site for Student Researchers, providing more interesting content than a standard online dictionary. Because the OED is concerned with word origins, I believe it would be helpful in creating bridges with ELL students as well, giving them a chance to see the linguistic contributions their language has made to ours. Check out the link in the lower center column for teachers and students (resources and lesson plans).