Saddled with a boastful stepbrother he dubs ``Mr. Gifted,'' Andy's self-esteem has evaporated until he touches a mummy case. Somehow galvanized, he creates a brilliant mummy painting that elicits gasps of admiration, makes wishes that seem to come true, and substantially improves his grades. Is Andy being helped by the mummy's ka (soul), or is he helping himself? The story can be read either way. Woodruff lays on her serious themes with a heavy hand (Andy describes at length his feelings about himself, other characters, and his dead mother), but she has a delicious way with comedy: Andy's torn between wishing for baseball cards or world peace, and his best friend's Egypt project is a hamster mummy reverently laid out in a Cracker Jack box complete with the unwrapped prize as ``a supreme gesture of respect.'' Predictable but likable, though the premise has been mined with more suspenseful results (e.g., in McMullan's Under the Mummy's Spell, 1993). (Fiction. 9-11)