Experimental designs address themselves to two concerns: providing answers to research questions and controlling variance. The latter involves threats to internal and external validity. The threat to internal validity constitutes the greatest difficulty because of maturation, history, experimental mortality, and differential selection. Examples of eight basic research design paradigms are made, pointing to the relative strengths of design in maximizing experimental variance and minimizing extraneous and error variance. Of most concern is whether a particular instructional strategy is resulting in measureable results on the part of students. The following are elements of a successful research proposal: (1) the development of a clear statement of the research problem, including an explanation of variate and criterion variables in the study, type of relationship between the variables, and the target population; (2) justification for the research approach; and (3) development of a statement of operational research objectives and/or hypothesis. (CA)