I've always struggled with the best way to provide positive, individual feedback for assessments. For the most part, students complete assessments quite well. With the four or five students that struggle, giving them positive, constructive feedback is crucial.
Today, I created a video that discussed in detail steps to solve particular problems from the assessment.
I used SMARTboard notebook software, Camtasia, and a mouse.
Students watched at their own pace. After they changed the answers on their paper, I conferenced with them individual about specific questions pertaining to the concepts.
I believe this to be a better method than large group discussion with all 26 students. It doesn't force students who understand the concepts to view demonstrations of information they already know.