I’ve written in the past about sites that allow students and teachers to easily create, and take, online tests (Student-Created Online Tests). Since that post, I’ve learned about two additional free sites that provide that same capability.
One is ProProfs.Com and the other is SMILE from Michigan State University. Both allow you to create a variety of different kinds of quizzes and have it hosted online so others can take it. ProProfs is probably going to be a little easier for English Language Learner students to actually create quizzes that other students can try-out.