Karlie Kloss may be one of the most in demand models of the moment, but she’s still a down-to-earth girl. The Victoria’s Secret star, Vogue Italia cover girl and globe-trotting beauty spent yesterday in Harlem helping restore CITYarts’ Pieces for Peace mosaic at Jacob H. Schiff Playground. “If I can do this here, maybe I’ll retile my bathroom,” she told Page Six of the work organized by Bing and dosomething.org. “It’s not as hard as it looks. It’s kind of fun. It’s like arts and crafts,” she said. Kloss returned from Paris, where she walked in the couture shows especially for the event, but made sure to enjoy the City of Light. “I brought my sister with me,” she said. “We were total tourists one day, and we went to Versailles. We went home and watched [Sofia Coppola’s] ‘Marie Antoinette,’ like, ‘We were there, we were there.’ ” Kloss is looking forward to more family time this summer, booking dates for a trip to Denmark. “That’s where my grandparents are originally from, and I just booked for the entire family. We’re meeting relatives we never met,” she said.