We decided on brainwashing.
We come up with harder things for our kids to do at home, then "inform them" that it's a challenge, and that they LOVE a challenge.
Granted, DS7 has taken this to heart more than his younger sister. He does seem to enjoy a challenge.
DD5 is still getting the hang of "loving a challenge," but we help her along with the catch phrase, "I am NOT going to give up!" As Dude points out, this is sometimes more helpful for a gymnastics "challenge" than for math, but hey, she's still young.
