Described is a two-phase investigation of the electroacoustic status of hearing aids used by aurally handicapped students in the Los Angeles City Unified School District. The first phase is said to have involved field examination using portable electroacoustic equipment and the second phase to have included re-examination of 10% of the field tested aids in a laboratory setting with laboratory equipment. Results confirmed previous studies which reported large numbers of aids malfunctioning and a large number of aids worn with gain settings so low that they could not be expected to help the wearer. Among eight conclusions listed are that audiological service should include counseling and training of parents, teachers, and children in the care and use of hearing aids; that replacement parts, batteries, cords, earmolds and loaner aids should be provided as needed; and that electroacoustic evaluation of hearing aids should be made at least annually. (CL)