Parents of D.C. kindergarten students learned yesterday whether their children would be attending school full or part time. The notices came a week late - school opened last Monday - but school officials say confusion over enrollment figures caused the delay.

"Unfortunately, a lot of people don't register their children for kindergarten ahead of time," school board member Betty Ann Kane explained yesterday. Since schools with very large numbers of kindergarten students are not able to offer full-day kindergarten because of staffing problems, school officials needed to know the exact number of new children before determining schedules, Kane said.

"It did work a hardship on people, and I'm very sorry about that," Kane said of the week-long uncertainty in scheduling. "It was very confusing to working parents, who had been making plans and found out they wouldn't have a full-day kindergarten."

Kane said that in some cases, schools with excessive kindergarten enrollments were able to transfer some students to less crowded schools nearby, making more full-day kindergartens possible. These transfers, which are done only with the approval of parents, are designed to keep kindergarten classes at a maximum size of about 25 students.

"The desire was to eliminate waiting lists in the school system." Kane said, "and to have as many children as possible going to full-day kindergarten.