To maximize the number of students who obtain a high school diploma or its equivalent

President Bush has been working with congress on additional legislation such as the Teacher Incentive Fund that allows States and school districts to reward teachers who demonstrate results for their students and who make the tough decision to teach in the neediest schools. Bush is also working on a proposed new program to encourage math and science professionals to bring their expertise into the classroom as part-time teachers. The President calls on Congress to fund this program.
Many states are implementing programs that will take teenagers licenses from them if they drop out of High School before they turn 18. These states believe if a student drops out looses their licenses then it will motivate them to go back to school. So far it has been working, but unfortunately many students decide to just drop out when they are 18.
Many states are also adding legislature that increases the age of consent to drop out from 16 to 18. This helps solve the problem in the short run, but many students inevitably still drop out after they turn 18

The National Educator’s Association has proposed a 12 Dropout Action Steps Program.
Other ideas to explore:

Local/State/National Information

High School drop out rate: A student that leaves for any reason before graduation without transferring to another secondary school. This is any student who is not accounted for on the 20th day of school. This excludes students who are expelled from school, missing school for a serious illness, or if they have left the country. A student is considered a drop-out, however, if they transfer from a secondary school to an institution of higher education such as a community college.
Educational Reform
Educational Legislation and Budget
No Child Left Behind act
Elementary and Secondary Education Act
GED
RetentionSocial Promotion
Socioeconomic
Charter Schools
Freedom Schools
Student Success
Vouchers

"Dropout Factories," AP/Johns Hopkins University (There are 22 dropout factories in MA, four are in Springfield. In fact, all four high schools in Springfield have been designated thus. By comparison, there is only one in Boston.)
The Silent Epidemic: Perspectives of High School Dropouts — a report on the dropout crisis in American public education.
On the Front Lines of Schools: Perspectives of Teachers and Principals on the High School Dropout Problem: report that includes the views of teachers and administrators, perspectives.
A few organizations to contact for more information:

High School Drop-Out Prevention