For anyone following the 12.5" blocks, this information is for you. The cutting sizes are listed on the above photo.
The Kaleidoscope went together well enough. I used 12" squares to start with. When I was ready to cut out the kaleidoscope from the pinwheel I drew the 12.5" square with pencil, then BEFORE I cut it out, I stitched around the inside of the pencil lines. That is stay stitching for the bias block. Then cut it out on the pencil line.
That left a lot of waisted fabric. I started to make it out of 10" squares, which will get the kaleidoscope done, but by using the 12" squares, I got a lot of Bonus Blocks. Look out in the left overs... You can cut a 6.5" half square triangle from each of the corners. You can cut a 2 square from each of the sides and they can be sewn into a 4 patch squared up to 6.5". I liked the Bonus Blocks. The photo shows them. If you are not interested in these or are short of fabric, then 10" squares are adequate.
Jupiter