A Teacher Is Interested in the Effects of the Use

A teacher is interested in the effects of the use of programmed learning materials as supplementary aids in an advanced foreign language course. She is interested in the amount of foreign language vocabulary learned during one college semester. There are 92 students enrolled in four advanced French classes who are taught by this teacher. These students make up the subjects for the experiment. Two of the classes of students have access to the programmed learning material and the other two classes do not. Discuss an experimental design that would be appropriate for this situation. Is it necessary that the instructor use a pretest? Consider the matter of control. What procedures would be necessary for adequate internal validity? Comment on the external validity of this experiment.