The Grand Prairie Independent School District may change the times that schools start and end, Superintendent David Barbosa said. The proposed changes, he said, are simply a matter of money. Under the proposal, school start times would be staggered for students, depending on their grade level. For example, elementary students would start at 7:45 a.m., high school students at 8:15 a.m. and middle school students at 8:45 a.m. Currently, school starts at 8:10 a.m. for all students. Dr. Barbosa has also proposed staggering the end times. Kindergarten through eighth-grade students currently get out at 3:10 p.m.; high school students end the day at 3:30. Dr. Barbosa\'s proposal calls for elementary students to finish at 2:45 p.m., high schoolers to finish at 3:30 and middle school students to end their day at 3:45. District officials estimated that staggering the times would allow them to reduce their transportation staff by 10 employees and save more than $2 million in salary, benefits and bus expenses over the next five years. About 13 percent of high school students