A lesson in editing was learned from a study of errors made on a national mathematics test in Israel. Analysis indicated that the errors were often caused by careless printing of the test, misleading figures, poor designations, or ambiguous phrasing. (MNS)

A problem is discussed in which students investigate the properties of the perfect triangle. (MNS)

Abundant and deficient positive integers are investigated, with a computer program listed. (MNS)

Graph theory is promoted as a vehicle for using the discovery method. A lesson is presented to illustrate the method, and activities and questions for further exploration are provided. (MNS)

Constructions with transparent tape are described for bisecting a segment and an angle, copying a segment, and dropping a perpendicular. A proof is included. (MNS)

Euler's discovery about the centroid of a triangle trisecting the line segment joining its circumference to its orthocenter is discussed. An activity that will help students review fundamental concepts is included. (MNS)

Suggests activities which provide students with opportunities to give meanings to symbols and to find reasons for doing computations. Includes investigations with a pendulum, circular running track, salary increases, and container volume. Indicates that teachers should place less emphasis on drill and manipulation to give meaning to abstract…

The estimation strategies of "using compatible numbers,""averaging," and "rounding" are used. The first two worksheets review easy arithmetic facts and ask students to identify compatible numbers. Worksheet Three introduces averaging and provides practice with rounding, while the fourth worksheet contains problems for group practice. (MNS)

Explores a particular method of searching for roots that lends itself well to discovery learning through writing a computer program. The teacher-student interaction is given, and two computer program listings are included. (MNS)

A simply posed problem suitable for a class studying summations and series, a class in elementary computer programing, a high school mathematics club, or an individual study project is given, with solution and challenges. (MNS)

Calculating the deficit between big-league baseball teams, and using that answer to prove the relationship between games behind and the described deficit, are each considered. (MNS)

Provides a classification scheme for four-by-four magic squares. Presents some classroom activities. Introduces a notation system for individual cells in the square. (JM)

Encourages the use of the microcomputer to teach probability theory and concepts. Presents an instructional sequence and provides 10 activities, three of which have short programs listed. (JM)

A geometric task was designed to investigate the effect of the frequency of irrelevant features in learning a conjunctive concept. One hundred algebra students were assigned to one of four treatment groups. Frequency of irrelevant features affected the usefulness of negative instances. (MNS)

Many worthwhile mathematical activities can be generated by an overgeneralization. Some conjectures and their verification are described, with some exploration of historical procedures. (MNS)