Mother: Why did you put a spider in your sister's bed? Mike: Because I couldn't find a snake."" . . . ""Grandfather: Well, Habib, how is your position at school? Habib: Very fine, Grandfather--center forward in soccer and right back in studies."" . . . Compiled at the suggestion of UNICEF'S Anne Pellowski, this sportive collection of international children's jokes reflects both worldwide and more regional preoccupations. Family tensions and school performance are recurrent themes, enlarged here by Taback's loose-limbed illustrations. Several fall flat, many sound creaky, and a few seem to suffer translation problems; overall they feature accessible subjects and include a rounded assortment of joke types--tongue twisters, goon characters (not ethnic), limericks, ambiguous scratch drawings, counting out games, even an innocent-daring verse from Scotland about not shoving ""yet grannie aff the bus."" A few knee-slappers but mostly steady grins.