POD - Problem of the Day

I post a POD (Problem of the Day) on the board every day.  The students come into class, get
their POD sheet out,  and work on the problem as soon as the bell rings.  I use Powerpoint and have been doing this for several years.  As a result, I have tons of POD's already to go.  I think the Powerpoint program is excellent for this because it allows me to create (graphs & pictures) anything that I want the students to do. I can then save and reuse them the following year or copy and change the slide information and make another one similar to it if needed.   The POD usually takes 2-4 minutes to complete.  It can be practicing a concept that we are currently on, reviewing a concept that we covered earlier in the year, or a concept that they had last year but seem to need a little "brush up" on.   Each student has a POD sheet that has a Monday thru Friday box on both sides.  This allows the student to do two weeks worth of POD's on one sheet.  We collect he POD every other Friday for a grade.