Spring has officially arrived!  If only it really felt like it.  Anyway, here are some Hill happenings to get you through what we hope are the last coldish days of the season.  

Double Down With Roll Call The Roll Call Book Club continues at the Hill Center (921 Pennsylvania Ave. NE) Wednesday with Mark Halperin, co-author of “Double Down: Game Change 2012,” which provides a behind-the-scenes look at the 2012 presidential election. Co-hosted by our pals at Hooks Books, drop by at 6 p.m. to enjoy a lively discussion, wine, cheese and a free copy of the best-seller (on a first-come, first-served basis). Looking Back on the Clean Air Act As part of the 2014 Environmental Film Festival, the National Archives is showing a Charles Guggenheim documentary from 1979, “HR 6161: An Act of Congress,” which follows the passage of the bill to amend the Clean Air Act. Senator Edward J. Markey, a co-sponsor of the bill, will introduce the film. Bob Kaiser, senior correspondent at The Washington Post, will discuss and take questions about the 58-minute doc afterward. It’s showing in the McGowan Theater (700 Pennsylvania Ave. NW) at 7 p.m. Thursday.  

Debating for D.C. The Sixth & I Historic Synagogue (600 I St. NW) and the Jewish Community Relations Council of Greater Washington are co-hosting one of the last debates Thursday for District of Columbia mayoral candidates before the April 1 primary.  Those in attendance will have the opportunity to ask questions of the candidates.  Doors open at 6:30 p.m. and the debate, moderated by Will Sommer of the Washington City Paper, will begin one hour later.  If you’re planning on attending, you’re asked to RSVP .  

For the Nerds Interested in quantum physics?  How about neuroscience? Well, string theory co-founder Michio Kaku will be at Politics and Prose (5015 Connecticut Ave. NW) on Friday discussing his latest book, “The Future of the Mind: The Scientific Quest to Understand, Enhance, and Empower the Mind.” Telekinesis, new ways to think about consciousness and the recording of dreams into realities are just a sampling of the subject matter. The discussion begins at 7 p.m. and beer and wine will be available.