The Butterfly quilt block has a lot of impact for such an easy block.  This is a 4-patch quilt block with nothing but 2 solid squares and 2 half square triangles.  Some quilters call this a 2-patch, but again, as with other 2-patch quilt blocks, it is often just grouped in with the 4-patch blocks.

The great thing about a simple block like this is that if you make it large enough, you can display some of your larger prints and novelty fabrics.  This is a great block for a scrappy quilt and also for sampler quilts.

Click on the link for the half square triangles and review that page if necessary.  Decide on the size of your blocks, and make your patches and cut your squares.

Sew them together using good piecing techniques, and you are done.

Here are some other design possibilities with a whimsical theme.  If you don't want your quilt to look too busy, and want to use a lot of fabric with busy prints,  think about putting lattice between the blocks.