A few weeks ago Jeffrey Hill informed on The English Blog about Sound Grammar.
This is a site that offers grammar lessons (so far 31) in an original way. The grammar point is introduced in a short dialogue at the beginning. A listening comprehension check follows together with some short explanations about the grammar point in question. Finally there's a grammar practice activity.
Most of the lessons come complete with a video where the grammar point is also explained and Sound Grammar allows you to download the audio file of the conversation. A transcript is also available.
The layout of Sound Grammar reminds us of elllo, which is always a guarantee of quality and originality.
Intermediate students will greatly benefit from the site, although some of the lesson are also within the grasp of lower level students.