Abstract: The specification discloses concrete forms each including a plurality of rectangular panels secured edgewise together by connectors. Each connector includes a pair of half sleeves secured in a pair of grooves in the edges of the panels, and a cupped head of a connector sleeve wedges the half sleeves together to hold the panels in edgewise abutment. A nut screwed on the connector sleeve draws the cupped head into wedging engagement with the half sleeves. Tie rods extend through the connector sleeves. The panels include wood framing having plywood faces and filled with foamed plastic.