WASHINGTON - Education Secretary Arne Duncan has some suggestions for how schools can spend their windfall from the economic stimulus law, including summer school and extra pay for teachers to coach struggling colleagues.

The nation's schools will get an unprecedented amount of money about $100 billion, double the amount of education spending under President George W. Bush over the two-year life of the new stimulus law.

The Obama administration has said generally how it wants the money spent, and it has warned states not to use the money to plug budget holes, despite loopholes created by Congress that would allow that to happen.

"You can identify your best teachers and pay them to coach their colleagues who are having trouble," Duncan said in prepared remarks. "You may have to scale this down after two years, but it can really help your younger teachers get up to speed."

Duncan also recommended adding afternoons, weekends and summer days to the school calendar: "Our school day, week and year is too short as it is. Many kids just need more time on task," he said.

The education secretary listed several ideas that, where they have been tried, have shown they can help kids learn. They include:

n Sophisticated evaluation systems for teachers and principals.

Extra pay to reward excellence in teaching or to lure teachers and administrators into struggling schools.

New charter schools.

Closing failing schools and reopening them with new staff.

More technology for classrooms along with training for teachers.

Modernized science labs and other facilities.