Algebra Equation Builder app

Stumbled across this nice app.  It has 4 levels which increase in difficulty and requires people to take four terms and arrange them with two terms on each side of the equal sign so the equation itself is true.  Level one only uses numbers and when done, you move to the next level which includes a variable and tells you the answer.  Thus as students move through the levels, the difficulty increases until you have to come up with some rather complex problems.  I found some of the problems to be rather challenging and I think this game would give students a chance to practice without it being too easy.
Change of subject.  I got trained in Apple configurater so that next week I can start getting my iPads and the elementary school mini's set up and running.  So my prep periods will be spent getting the iPads up and running so I can actually begin using them in the classroom.