Terence, do you provide any other exam training resources? For some students that have been out of school for several years the actual mechanics of test taking can be a challenge. You may consider just taking a single session you would use for a quiz and take your students through some best practices in how best to take a test. Sounds a bit silly but for some students and this can be the case with more than you think, just knowing how to be a good test taker is just as important as knowing the material.
James Jackson