Kevin Federline -- I RIDE WITH JAMES HARRISON ... Participation Trophies Are Dumb

You've heard from athletes, pundits ... even Rush Limbaugh ... but now the question -- how does Kevin Federline feel about James Harrison's anti-participation trophy stance??

HE LOVES IT!!!

We were talkin' football with Federleezy on his way out of Boa Steakhouse on Sunset Blvd. when he applauded the NFL star for making his kids give their trophies back.

K-Fed knows a little something about parenting ... he's got 6 kids ... and says it's important that all of them understand how the real world works.

"Don't give 'em something, make 'em EARN IT."