Classroom motivator

I've struggled this year with my students turning in homework. I'm fully aware of the research that traditional homework in elementary school isn't very beneficial, but their homework is reading logs (we expect nightly reading) and math review.  

Instead of being negative and always assigning detention, I've decided to try a more positive approach instead.

Each week that my students bring back their completed homework, they will earn a piece toward our Mr. Potato head.  When our spud is fully assembled, they'll earn a prize.

However, I didn't go for any ordinary Mr. Potato head.  Oh no, I ordered this mermaid version instead:

We shall name her Ursula and she shall have a place of honor in our classroom!  Amazon will deliver her next week :)