Please follow the directions at Cluck Cluck Sew for completing your blocks. Bring your blocks to the February meeting, This is a great opportunity to make additional blocks for yourself, all year long.
The tutorial doesn't include 12.5" blocks, here are the measurements for the fabric pieces:
Focus fabric, cut 2 - - - 6.5" x 12.5"
Background, cut 2 - - - 6.5" square
Background, cut 4 - - - 2.5" square
As an alternative, you could make four 6.5" blocks and join them for a 12.5" block.