More than 29,000 Maine students are missing enough class time to cause worry among school administrators and state education officials responsible for helping them succeed. The Maine Department of Education last week released 2016-17 school year data for districts across the state that show that 16 percent of the nearly 192,000 students included in the data are chronically absent. “To be honest, it’s higher than we anticipated it being,” said Janette Kirk, the DOE’s deputy director of learning systems. Research shows that students who miss that many days lag behind their peers, run the risk of becoming disengaged in school or dropping out, and are more likely to fail classes.