Student groups use whiteboards for warm-ups and review during lessons.  Using whiteboards serves as an effective use of materials for assessment during lessons.  When students respond to questions on the white board, I am able to scan the entire room immediately for understanding.  I provide students with immediate feedback with a "thumbs-up" or "thumbs-down" gesture before providing all students with the correct response.  Thus, I am able to view each students' understanding and moniter their learning.  Furthermore, I use physical gestures to monitor student understanding.  Students respond with a "thumbs-up" or "thumbs-down" to agree or disagree with a verbal prompt.  Again, this technique allows me to effectively and efficiently monitor student learning during a lesson.