This is paper pieced (Yes, I know, I paper pieced!) but in the realm of paper piecing it is easy because all the bits except the centre are rectangles. Not difficult to get the size right at all. Aylin has made a quilt with all different sized bubbles. You can see it here - http://aylin-nilya.blogspot.co.uk/2015/02/bubbles-quilt-pattern.html (If you are interested in having the pattern for yourself, Aylin has a link to her shop at Payhip on her blog.)
I really like the pattern but time constraints mean I can't finish it today. In fact I will be away from my sewing machine for eleven days. I will also be away from wifi most of that time. Eeeek! I keep telling myself that it will be good for me but I am sure I will be found pressed up against a window in the corner holding my phone up trying to get a signal like the desperate person I am. Sad but true.
Hope you all have a great half term, if that applies to right now.