Regular pentagons do not fit together by themselves. You have to use other shapes to fit them together.To make this piece I used an enlarged photocopy from this Dover book...
Here it is part completed shown from the back.
After I had completed the middle section the shape reminded me so much of the English tudor rose.
The appliqué is slightly wonky - I will have to fix that when I trim the blocks.
I'm still working on enlarging the other pieces and I have three more star shapes to make before I have enough for a 5 ft square quilt. Now up to 753 pieces overall - I expect I will make 1000 for the finished quilt. Linking up for the Monday Morning Start Count at Life Under Quilts.