Teachers at a Skokie school forced a 6-year-old with a broken leg and a concussion to crawl back to his classroom across an icy playground, then failed to call for an ambulance, according to a lawsuit filed Tuesday. Kindergartner Rahul Chandani slipped on a mound of snow and hit his head in the playground at Devonshire Elementary School on Jan. 3 last year, but didn’t get any medical help until his mom came to get him, the lawsuit filed in Cook County circuit court by Chandani’s parents Pritam and Priya alleges. “His teacher told him, ‘You’re a big boy —...