Reports an experimental study of 80 ninth grade biology students randomly assigned to treatment and control groups to determine whether the use of human examples in instructional strategies on Mendelian genetics increases acquisition and retention of genetics concepts. Results indicate that use of human examples in contrast to traditional examples…

Presents a study to evaluate the cognitive level of questions in middle school science textbooks. Questions and their location were coded from six randomly selected chapters in eight middle school science textbooks. Results indicated that input level questions were the dominant question type, probably leading to students functioning at lower…

Reports a study of 913 Israeli students in grades 7-12 from randomly chosen heterogeneous homeroom classes to investigate students' Piagetian cognitive levels using a video-based test. Results indicate that less than 50 percent of high school students have mastered formal operational reasoning. (MDH)

A study interviewed 6 grade-6 students after participation in 21 lessons on basic concepts of fractions and decimals to determine how different children construct rational number concepts. Discussed the formation of the key concept of equivalent fractions based on student responses to interview questions. (MDH)

Describes three perspectives from which middle school teachers can plan laboratory activities for the purpose of improving students' scientific literacy. Perspectives are the learning cycle approach categorizing activities by stages of development; problem-solving skills approach categorizing activities according to the amount of teacher control;…

Presents a study to examine the effects of a verbal teaching strategy versus a strategy providing instruction using activities and manipulatives in four seventh grade earth science classes with students of varying cognitive abilities (n=83). Results indicate that students with more cognitive structures perform better and that using manipulatives…