The wall sit is one of my favorite exercises. You can really feel it burning and you can see and feel your knees shaking. I think it’s a great workout, and I’m excited to take this challenge on this month. 
Just in case any wants a picture of a wall sit here ya go. Remember to maintain the 90 degree angle the entire time. 
30 Day Fitness Challenge also gives a guide and video of how to do a wall sit.
Say Yes to Happy 