President Bush called Monday for improvements in the 38-year-old Head Start (search) program, declaring it vital to the country's future that 1 million 3- and 4-year-olds from low-income families have the learning skills necessary for school.

Head Start efforts are "working OK," but "we want them to work better than OK," the president said at a Head Start center at Highland Park Elementary School in this Washington suburb.

The school event was Bush's only public appearance before his departure Monday evening on a five-country trip to Africa. With his re-election campaign formally under way, Bush has sought to keep a focus on domestic issues such as welfare reform, Medicare and Head Start, juggling foreign policy priorities like his trip to Africa and Iraqi reconstruction.

Evidence shows children in the program do better in school than other poor children, but not as well as their more affluent peers.

Supporting proposals that are drawing some controversy, Bush and House Republicans want to give a handful of states the option of taking over Head Start programs now directed by the federal Department of Health and Human Services (search). The idea would be for the states to blend such programs with existing state-financed preschool programs.

"We want Head Start to set higher standards for the million children it serves," said Bush. "No one wants Head Start to change; we just want additional focus."

"In my line of work, you see a problem, you address it," he added.

Critics fear a declining federal role will result in a lowering of standards and they say the program would lose its comprehensive mission of health, nutrition and parental involvement. Opponents also worry that states would use the federal dollars to cut state preschool funding.

White House spokesman Ari Fleischer dismissed criticism of the president's proposal as coming from "a very small but liberal faction." Fleischer said the administration's proposals have bipartisan support from the nation's governors.

Some tensions stem from the divide between a conservative administration directing the program from Washington and the many liberals who operate individual centers under government grants. The nonprofit groups that run the programs are closest to Head Start, but they could lose their centers if the Bush plan goes through and states are free to contract with whomever they choose.

Almost 70 percent of children enrolled in Head Start are minorities, including about a third who are black.