In emphasizing the potential of electronic media, Prof. Greenfield (Psychology, UCLA) tends to underestimate their more questionable effects--discouraging reflection, for example--and to overlook the implications of those effects. And in generalizing from the little systematic-research (even from responses to single episodes of All in the Family or Happy Days), she makes her arguments more vulnerable to criticism. Nonetheless, this includes some persuasive evidence--like the power of visual movement as a learning tool--and offers some surprising material, including an engrossing analysis of the cognitive processes required for Pac-Man. Greenfield believes that TV per se is not detrimental, but may be in how it's used. Though heavy watchers seem to develop better visual skills than light or non-viewers (e.g., an ability to grasp information from films), they also use more ""vague references"" in their speech, much like TV dialogue. Furthermore, while programs like Sesame Street strive to make children active participants, more Children watch adult films, a largely passive experience. Video games, too, have their problems--undesirables in the arcades, most prominently--but their learning possibilities are impressive and they turn passive viewers into more active participants. The amounts spent to learn a game may be greater than Greenfield calculates; still, she clearly understands the personal rewards mastery brings. And she rightly emphasizes the need for games that feature non-aggressive themes and cooperative play, and that appeal to the fantasies of girls; for many, video games are an informal introduction to computers, a fast-growing field still open to women. Computers, she finds, are more promising still, both those offering programs suitable for practicing skills and word processors that allow students to revise almost painlessly. Less persuasive overall than other volumes in the Developing Child series--the research is flimsier--but not without interest to print champions as well as software specialists.