The Montgomery County Board of Education unanimously approved changes yesterday to beef up kindergarten academics. Quiet time, music time, art time and exercise time are out. Reading, math and social studies are in.

The move was pushed by Superintendent Jerry D. Weast, who has made early childhood education a priority. His $1.2 billion operating budget and his capital improvement spending plan call for expanding the number of all-day kindergarten programs from nine to 28 of the neediest schools, building early childhood centers and lowering average class sizes from about 20 students to 17. The curriculum change will affect both all-day and half-day kindergarten classes.

Weast cites Montgomery County's screening tests, which show that even in kindergarten, African American and Hispanic students tend to lag academically behind their white and Asian classmates. With more intense kindergarten instruction, he hopes to begin to close that achievement gap before it grows wider.

"The research shows that children learn early, that children are much more able to absorb concepts much earlier than we thought," Weast said. "Expensive day cares have been selling this kind of instruction for a long period of time. It's about time we provided it for all our children."

And, said school board member Nancy J. King (Upcounty), it is simply a different world.

Initially, kindergarten's purpose was to get children ready to come to school, to spend a few hours in a classroom and to learn how to socialize with classmates.

"But now we're expecting more of our children," King said. "We need less play time, like in preschool, and more learning time. But it needs to be done right."

Studies have shown few long-term benefits from all-day kindergarten classes, noting that they offer the same curriculum as half-day kindergarten, only twice as long.

"The bottom line is that long-term effects from kindergarten have as much to do with the quality of programming as the length of the school day," said Fran Bridges, a school official who studied kindergarten curriculum.

Weast, who said the current kindergarten curriculum "lacked comprehensiveness" and was "insufficient," plans to change that, starting, he hopes, next fall.

In his plan for revamping kindergarten curriculum, Weast calls for some of the same techniques that teachers use in elementary schools: accelerated instruction, grouping by ability and extended time for reading, writing and math.

While kindergartners in all-day programs spend more than three hours a week doing art projects, Weast's plan eliminates art as a separate subject and incorporates it into other subjects. Music classes will be cut from about three hours a week in all-day programs to little more than an hour. Half-day students will have just 35 minutes of music a week. The same is true for physical education.

Time spent on reading will nearly double, to more than five hours each week for half-day students and 10 hours for all-day kindergartners. Likewise, time spent on math problems will double to 2 1/2 hours a week for half-day kindergartners and more than five hours for all-day students. More time also will be spent learning science and social studies.

Linna Barnes, president of the Montgomery County Council of Parent Teacher Associations endorsed Weast's plan. One of her children was in an all-day kindergarten program, and one was not. "There was a world of difference in the way each one learned to go on," she said.

Still, researcher Fran Bridges said a better curriculum and a longer kindergarten day is only a start for disadvantaged children.

"The issues are much more complicated than we are ever willing to talk about," she said. "One year's worth of intervention in the lives of children whose lives are already challenged is not enough."

Laura SamPedro, now a senior at Springbrook High School and student member of the school board, recalled her kindergarten teacher reading "The Cat in the Hat" to her while her classmates napped.

"That's when I learned to love to read," SamPedro said. "Because I started reading so young, I could easily do my homework."

CAPTION: "Children learn early," said Montgomery County Superintendent Jerry D. Weast.