There are too many thoughts in that sentence; it's difficult to follow. And you're burying the point (or at least, what I think is the point.) Perhaps: We are motivated to do additional research on this approach, especially when we consider facts such as the high percentage of students that fail language courses, the number of students who remember nothing after an eight week course, and that English had the lowest scores of any subject in a recent national exam.

However, considering that many language courses have failed their students, with English being the worst-performing subject in the recent national exam and many students remembering nothing after an eight-week course, we feel motivated to research this approach further. [I've corrected it minimally. The clauses could also be reordered to make it flow better.]