It used to be your basic, boring downtown office building lobby. But last month, Angela Berger got an idea. The ground floor of 888 17th St. NW may never be the same.

"To liven things up," Angela, who manages 888 for the Brawner Company Inc., went and bought three dozen tadpoles. She installed them in the first-floor fish tank that until then had housed only a few goldfish. Then she sent memos to every tenant in the building informing them that the tadpoles had moved in, and asking for volunteers to adopt them once they became frogs.

The response has been "incredible," Angela says. "People in the building talk about them all the time, and they stop by to see them every day on their way upstairs to work." More lastingly, of the 31 tadpoles still alive (five came out second best in fights with goldfish), 10 have been promised homes by 888'ers.

The first adoptive tenant/dad was none other than Donald Dell, the celebrated lawyer and agent for tennis stars. Angela says she's never met a tadpole with a backhand, but, hey, you never know . . . .

Angela denies all rumors that the luncheonette in 888's lobby is going to put frogs' legs on the menu if 21 more volunteers don't step forward. But she would like to hear from anyone who wants to give a home to a tadpole who will be a frog by mid-July. Angela's phone is 298-6868.