The document discusses the differences between mistakes and errors in student work. Mistakes are slips that students can self-correct when pointed out, while errors require explanation. When responding to errors, teachers should provide feedback to help students improve rather than criticize them. Teachers can assess student performance through exams, comments, reports, and self-assessment. When providing feedback during oral work, teachers should consider the lesson stage, activity type, mistake made, and individual student. There are three techniques for correcting errors: self-correction, student-to-student correction, and teacher correction, with correction involving showing the mistake and helping the student address it.