The mean and median age of science and technology materials in the five middle school library collections located in the Springfield (Ohio) City School District were calculated. The percentage of books 10 years old or older was calculated. Science and technology were chosen due to the rapid amount of change in these areas. Three broad Dewey categories in the 300s, 500s, 600s, and the following three narrower areas were investigated: astronomy, space, and the solar system; general biology and ecology; and human anatomy, physiology, and hygiene. The mean age of books ranged from 13.5 years to 34.9 years; the median age ranged from 10 to 32 years old. The percentage of books 10 years old or older at each of the individual middle schools ranged from 45.8% to 87%. The findings reveal that the middle school library collections surveyed need new and updated materials. The outdated collections are unable to support curricular goals or student needs. Appendices include the data collection form and inventories showing total items in each Dewey category for each school. (Contains 15 references.) (Author/MES)