As usual, Peri is a font of intriguing lore: on the world's first birthdays, marking celebrated births; on birthstones and birth flowers, signs of the zodiac and horoscopes; on names--ordinary vs. unusual (and the possibility of changing an unwanted one). Also, of course: ""Why We Light Birthday Candles,"" play Pin the Tail on the Donkey and other guessing-the-unknown games; and how special birthdays are celebrated in various parts of the world (Japan's Seven-Five-Three festival, the Masai initiation, the Jewish bar mitzvah, the British ""key-to-the-house"" 21st birthday party). The intercultural element is intrinsic to Perl's purposes, and youngsters will quickly learn here how differently the same events may be marked. But there is also a sensible discussion of astrology, its origins and claims (""How well do you think your birth sign describes you?"" Peri inquires); and all sorts of curiosa about naming-customs that might also help children understand how they got their names. Like Pinatas and Paper Flowers, this sports perky, inviting line drawings. It could give enterprising teachers a lot of ideas, as well as enlighten kids.