Back to school lunch box notes meet cool science lesson

While looking around for cool printable lunch box notes for our back to school guide, I stumbled across these wildly awesome optical illusion flash cards at Mr. Printables. As a kid, I couldn't get enough of optical illusions and now my own girls feel the same way so I know they'd just love them. Use them as actual flash cards, or for fun, tuck them into your child's lunch box and you can follow up with a lesson on impossible shapes, paradox illusions, MC Escher, and peripheral drift patterns. Probably taught by your child.   Of course, scribble a thoughtful little note on the back to personalize it. Maybe something like, how you really hope your child is drinking enough H2O at lunch and that just because it's in a tall skinny glass doesn't mean it's more water than if it's in a short, fat glass. Find the free printable optical illusion flash cards at Mr. Printable