The U.S. must improve its educational standing in the world by rewarding effective teaching and by developing better, universal measures of performance for students and teachers, Microsoft co-founder Bill Gates said Tuesday, reports the Associated Press. Speaking at the National Conference of State Legislatures’ annual legislative summit, Gates told hundreds of lawmakers how federal stimulus money should be used to spark educational innovation, spread best practices and improve accountability. Gates, one of the world’s richest men, has been a longtime critic of American public schools and has used philanthropy to advocate for a better educational system. U.S. schools lag their international counterparts because of "old beliefs and bad habits," and it’s not clear how to get them back on track without uniform achievement standards, he said. "We don’t know the answers because we’re not even asking the right questions and making the right measurements," Gates said.