IN Los Angeles, there are two things residents don't take lightly: anyone who messes with their homes or the schools their children attend. Thus it is not surprising that emotions are running deeper than an inkwell following the Los Angeles school board's decision this week to put all schools on a year-round schedule.
The move buttresses a nascent but growing trend in American education to move away from the traditional school calendar.
But it also ensures that tens of thousands of students, teachers, and parents in the nation's second-largest district will have to make major adjustments in their lifestyles over the next few years.
Proponents see it as the fairest way to help meet what they call an overcrowding crisis in the city's schools.
But critics, many of them suburbanites who view year-round schooling as disruptive to family life and vacations, vow to fight the plan. They predict an exodus of children from public to private schools as a result of the biggest education controversy here since mandatory busing.
``I think you are going to see a huge brain drain out of the Los Angeles Unified School District,'' says Barry Pollack, a parent.
About one-quarter of the district's schools now operate on year-round calendars. The board's decision, on a contentious 4-to-3 vote, requires all 646 schools to switch to year-round education beginning in 1991.
Schools can chose single-track, in which students would have six weeks off in the summer and another winter break, or multitrack, in which pupils are divided into four groups with one group off at all times.
Most are expected to adopt the single-track approach, which more closely resembles the traditional calendar. But this option does not save seats in the classroom. Thus schools will have to try to expand their capacity using other methods, such as setting up portable classrooms. If they can't, they will have to go to the more controversial multitrack, which increases classroom space by one-third.
Even before the vote, Los Angeles had more schools on year-round schedules than any district in the country. Its future in converting the whole district may influence whether other communities decide to move away from the traditional summer vacation.
``Everybody will be watching to see if it works,'' says Mary Ellen Parker of the National Association of Secondary School Principals.
Some 631 schools nationwide are currently on year-round calendars - less than 1 percent of the education system. Even so, that represents a 25 percent increase over last year.
Most of the schools changing to the new schedules are in the South and West, where enrollments are surging. Advocates of year-round classes argue it enhances student achievement, because pupils tend to forget less when vacations are staggered.
Little was said about test scores in the debate over conversion in Los Angeles, where lack of seating was the main impetus. Projections show the district will have to make room for 62,000 more pupils between 1991 and 1993. High birth rates and an influx of immigrants underlie the boom.
More than 24,000 children are now bused from overcrowded neighborhoods, mainly in the minority-dominated inner city, to less-crowded schools in outlying areas. But district officials contend that will not be enough to handle future increases.
In a debate that at times took on racial overtones, board members who supported the move have argued that the most equitable way to deal with the problem was for all schools to convert.
But opponents in suburban areas say the district's failure to plan for inner-city children's needs is no reason to punish the middle class. Their objections: Year-round schooling complicates summer vacations, forces pupils to attend classes in non-air conditioned schools, and makes it hard for students to participate in extracurricular activities.
Some parents want to pressure the board to overturn the decision. It did that in the face of public pressure two years ago. But few expect it to this time. There is talk of ``seceding'' from the district.
Other opponents seem resigned to try to make the system work. ``We have to push more to find solutions,'' says Pam Bruns, a parent in Pacific Palisades.
Students, too, are preparing for changes. Alexis Allen, a fourth-grader at the Sherman Oaks Elementary School, worries about ``missing out on activities in the summer.''
But fifth-grader Steven Harriton, in high-top Nikes, eagerly awaits the new regimen: ``Sometimes I get bored after being off three months.''