Even Boredom Beats the Books : Vacation: Some teen-agers complained there was nothing to do. Others hit the water. And mall-hopping was on the decline.

Spring break is delightful. Spring break is boring. It’s running full-speed into the lake at the Santa Fe Dam Recreational Area, hitting the water like a cannonball. It’s sitting in the Santa Anita Fashion Plaza with a friend and wondering aloud: “Is this all there is?�

“I thought it would be fun, but there’s nothing to do,� said Kristina Camerano, 15, a sophomore at Mission High School in San Gabriel.

Kristina and fellow student Annette Llamas, 14, were perched at the edge of a mini-playground, watching Kristina’s 7-year-old sister, Kimberly, work out on some climbing devices.

The mall’s daytime pianist, Norma Juico, had just launched into a lavish arrangement of “Blue Velvet� on the baby grand, and the two teen-agers were catching up on gossip, they said.

And the prospects for the rest of the week looked uninterruptedly monotonous. Any big plans? “A wedding,� Kristina said.

Spring break is a time when kids sleep late and float through long structureless days.

In the San Gabriel Valley and Glendale areas, it’s also a time when the lifeguards at the Santa Fe Dam keep an especially sharp eye out (there were four near-drownings and a person hit by a rock Sunday), merchants in the Arcadia and Glendale malls watch parades of non-buying browsers march through their stores and parents search frantically for new ways to keep the kids busy.

Last week, when most public schools were out, Raging Waters was the hot spot. The San Dimas amusement area opened for a full week, offering a cornucopia of teen-oriented activities, including a bikini contest, a search for would-be models and a reggae band.

But then, Kristina and others noted with dismay, the place closed down on weekdays until June, just as private and church schools were letting out.

That left Santa Fe Dam, a broad, flat area at the mouth of San Gabriel Canyon in Irwindale, with bicycle paths and picnic areas. The big attraction is the lake, where posses of kids race in and out of the water.

No boredom here. “Everybody needs a break sometime,� said Nelson Mota, 15, a Baldwin Park High School freshman, leading a breakneck charge of siblings and cousins into the lake.

For his 6-year-old cousin, Rigo Torres, there was even the promise--no, the hope, interjected his cousin--that his mother would take him to Knott’s Berry Farm later in the week. “She said maybe,� Nelson said.

In the canyon itself, where winter rains have turned the San Gabriel River into a torrent, some student vacationers settled at the edge, dipping a finger or toe into the frosty water or throwing out a fishing line.

“This was a last-minute thing,� said Oneyda Hernandez, 15, a Baldwin Park High School sophomore, strolling with friends along the bank of the river’s West Fork. “We were going to the beach.�

“Then we decided there would be too much traffic coming home,� said Rudy Romo, 19, a Mt. San Antonio College student.

The principal activity here is to wend your way to a boulder in midstream and lie back--or “kick back,� as several teen-agers put it--and watch the water rush past. For the more action-oriented, there are snakes in the bushes, said Charles Munoz, 13, a seventh-grader from Hesperia. “My brother found a three-foot garter snake,� he said. “He let it go.�

Maybe it’s the recession. Or maybe it’s because there are flashier attractions elsewhere. But there are signs that teen-age mall-hopping, at least in the springtime, may be on the ebb.

At the Glendale Galleria, a group of students from Notre Dame High School in Sherman Oaks watched the slow flow of shoppers and planned to head for a movie.

How does the galleria stack up as entertainment? T. J. Picar, 17, a husky boy with his hair buzzed off at the sides, gave the scene a sour once-over.

“It’s gettin’ old,� he said.