As to woods, 1x anything is fine. I start my students (I teach high school
shop) cutting heart shaped patterns out of a 3/4", 5 1/2" x 5 1/2" square.

You're having high school kids cutting out HEARTS?!?!? What an ass
hole. :-)

Seriously though, why not have them cut out Chevy bow ties or Ford
ovals, or Mopar rams, or . . .something else they can relate to better?

Wayne