As we celebrate the 250th anniversary of the Declaration of Independence, there’s growing debate about how schools should teach what it means to be American. That made it a terrific time to check in with Richard Kahlenberg, the director of the American Identity Project at the Progressive Policy Institute, where he researches how public education can help strengthen American identity. Kahlenberg, a proudly old-school liberal, has authored many influential books on K-12 and higher education, including Tough Liberal, his compelling biography of AFT founder Al Shanker. Here’s what Kahlenberg had to say.