Most of the activities suggested in this trial version of the Genetics unit produced by the Australian Science Education Project rely on second-hand data, although one of the introductory activities suggested is based on results of a mouse breeding experiment. The unit is, therefore, expected to be suitable only for students who are capable of abstract reasoning. The unit consists of a general introduction, followed by nine options, the first two of which are designed for the slower learners: "A Happy Medium" (incomplete dominance); "The More the Merrier" (polygenic inheritance); "Heredity or Environment?""The Imperfect Copy" (mutation); "Genetics and Disease;""It's a Woman's World" (differential death rates between the sexes); "Your Family Tree;""How Different Are You?" and"Crossword" (a summarizing unit). The introductory section contains exercises introducing the basic concepts of Mendelian genetics and the chromosomal basis of inheritance. The teachers' guide is an overprinted version of the students' manual, including comments on the introduction of the unit, possible discussion questions based on ethical implications of genetics, lists of necessary apparatus, and a select bibliography. The students' record book contains worksheets for most of the options and other activities. (AL)