Awesome strategy where students use cards to indicate how they are progressing through the independent practice. This allows the teacher to intervene when necessary and gauge student's understanding of concepts.
Use green, yellow, and red colored cups for group work. When a table gets too loud, change the cup to yellow. If the table continues to be too loud, the cup gets changed to red; this means a loss of group time. Students now have to do their work independently and silently. This is great and won't punish the entire class.