WASHINGTON-  President Barack Obama on Saturday said he will send to Congress this week a blueprint for overhauling the nation’s education program and the No Child Left Behind project to improve schools, support teachers and set standards that will give high school graduates “the best chance to succeed in a changing world.”

Worried that the U.S. is falling behind in education, Obama warned in his weekly address that “the nation that out-educates us today will out-compete us tomorrow.”

He said America has “lost ground” over the last several decades, pointing to 15-year-olds who no longer are near the top in math and science compared to their peers around the world, high school graduation rates that have lagged behind those in most other wealthy countries, and a United States that no longer leads the world in producing college graduates.

“Unless we step up, unless we take action,” Obama said, “there are countless children who will never realize their full talent and potential.”

On the Republican side, Sen. Scott Brown, recently elected from Massachusetts, said in a GOP response to the president’s remarks that Obama in the first year of his administration spent too much time and energy on health care and other issues and not enough at trying to end the current economic recession.

Brown said that “an entire year has gone to waste. Millions of Americans have lost their jobs, and many more jobs are in danger. Even now, the president still hasn’t gotten the message.”

Obama said he will push education reforms that insist the states ensure high school students are ready for college and careers by the year 2020, and stress academic achievements beyond what were called for under President George W. Bush’s No Child Left Behind program.

Secretary of Education Arne Duncan, speaking to reporters on Friday, said the No Child Left Behind law, passed in 2002, has resulted in a lowering of standards and that teachers spend more time in class preparation than in actually teaching in the classroom.

Duncan has begun working with a bipartisan group of Capitol Hill lawmakers in trying to rewrite the law, and he plans to tour schools in Iowa with Democratic Sen. Tom Harkin of that state, chairman of the Senate Education Committee.

How the proposals will fare in Congress is uncertain.

Some teachers’ union officials, who have previewed the plan to be unveiled Monday, said the proposals could end up just rewarding the top 10% of schools.

Randi Weingarten, president of the American Federation of Teachers, said an initial review of Obama’s plan shows that it is titled against teachers and makes them the sole “scapegoat” if students’ test scores do not improve, much more so than principals, school administrators, parents and the students themselves.

“This blueprint places 100 percent of the responsibility on teachers and gives them zero percent authority,” Weingarten said.

“For a law affecting millions of schoolchildren and their teachers, it just doesn’t make sense to have teachers and teachers alone bear the responsibility for school and student success.”

• Richard A. Serrano