Quick Tip: Take A Number

Early in my teaching career I had the problem of several students wanting help at the same time.  Students would  sit at their desks with raised hands or stand in line at my desk.  Students wasted a lot of time waiting for help.  To address this problem, I used a “Take A Number” strategy.  I made a set of laminated cards individually numbered from 1-20.  The cards rested in a little box on my desk in numerical order with the number 1 card on top. Rather than standing in line or raising a hand, students took a number and then went back to their seats.  Once they returned to their seats they were expected to work on any other tasks they understood until their numbers were called for help.  It worked great for me!  Do any of you have other strategies for this type of problem?