Multiple-Choice Tests
Both versions of the multiple-choice test (A and B) included 30 items, with half of the
items measuring simple knowledge and the other half integrated knowledge. Most of the
questions were adapted from those used in various international, national, and provincial
science assessments that are now in the public domain.
The multiple-choice tests were administered 3 weeks before instruction began (pretest),
immediately after completing the unit (immediate posttest), and again 6 weeks later (delayed
posttest). Class A wrote version A in the pretest, version B in the immediate posttest,
and version A again in the delayed posttest. In contrast, class B wrote version B in the
pretest, and versions A and B in that order after the intervention. Content validity of the
test items was established by a group of experts in science education. The Pearson correlation
coefficient was 0.67 for simple knowledge, 0.65 for integrated knowledge, and0.80 for total knowledge. McMillan and Schumacher (1989) indicated that a coefficient of 0.70 is acceptable for research purposes. These correlations were deemed acceptable
given the exploratory nature of the study.