Percentages in some categories were so low or negligible that they may not appear on Fig. 2. Performance expectations as defined in the TIMSS study are as follows: Simple information (information such as vocabulary, facts, equations, simple concepts; examples include defining, describing, naming, quoting, reciting, etc.; specific examples are defining scientific terms [boiling point, niche], knowing symbols [abbreviations for units, chemical symbols], describing simple concepts [materials expand when heated, characteristics of animals]); Complex information (information involving the integration of bits of simple information; examples include differentiating, comparing, contrasting, synthesizing; specific examples are understanding how increased external pressure raises boiling point of liquids, how fire is a part of the life cycle of pine trees) (Robitaille et al., 1993).