After presenting a general linear model as a framework for discussion, this paper reviews five methodology errors that occur in educational research: (1) the use of stepwise methods; (2) the failure to consider in result interpretation the context specificity of analytic weights (e.g., regression beta weights, factor pattern coefficients, discriminant function coefficients, canonical function coefficients) that are part of all parametric quantitative analyses; (3) the failure to interpret both weights and structure coefficients as part of result interpretation; (4) the failure to recognize that reliability is a characteristic of scores, and not of tests; and (5) the incorrect interpretation of statistical significance and the related failure to report and interpret the effect sizes present in all quantitative analysis. In several cases small heuristic discriminant analysis data sets are presented to make the discussion of each of these five methodology errors more concrete and accessible. Four appendixes contain computer programs for some of the analyses. (Contains 19 tables, 1 figure, and 143 references.) (SLD)