I started playing the piano 4 months ago and have reached the stage where I can play some basic chords with my left hand and at the same time notes with my right hand. I'm using the Complete Keyboard Player book 1 by Kenneth Baker and I've reached about two thirds of the way through. Obviously the further I progress in the book the more difficult the pieces become, so the longer it takes to master each piece.
Is it OK to begin to play the pieces further along in the book before the earlier one is completely mastered, thereby giving my practice sessions some variety? Or should I stick with the each piece until it is perfect each time I play it? I'm tempted to try the later pieces but I don't want to get things out of sequence and learn the wrong techniques.