 FINALLY TONIGHT, FOR A CROSSING GUARD, BEING QUICK ON YOUR FEET IS A PLUS. ONE WOMAN HAS BEEN DIRECTING TRAFFIC WITH RHYTHM AND STYLE AND DELIVERING SMILES FOR MORE THAN A DECADE. IN OUR WEEKEND JOURNAL, CBS NEW YORK'S STEVE OVERMEYER INTRODUCES US TO THE STREET STAR. SCHOOL IS OUT. AND FOR STUDENTS, CROSSING THE BUSY STREETS OF BROOKLYN CAN BE NERVE-RACKING. BUT IN THE DISTANCE, THESE KIDS SEE SOMETHING FULL OF JOY.