Each year, 2.5 million children in the U.S. go to sleep without a home.
The Boston Celtics took a break from practice to play with the kids from Horizons for Homeless Children.
Center Kelly Olynyk supervised the slide area while rookie point guard Marcus Smart blocked some kids' shots.
The Massachusetts non-profit offers early education, family support services and opportunities for play.
But they need your help. You can help a homeless child get school ready. Donate now at horizonschildren.org.