Chemistry students in SSII in each school were used for the study. With the assistance of their Chemistry teachers the
students were given the pre-test to ascertain uniformity of their entry level during the first week of the experiment. The
schools were randomly assigned to the different concept-mapping strategies viz: spider, flowchart and hierarchical.
The treatment commenced a week after the administration of the pre-test. In the first week of the treatment, all the three
groups were introduced to the concept mapping methods and the prepared concept maps were distributed and
explained to them. The following week, teaching started in all the groups. The treatment lasted for five weeks in the
three schools.
After the treatments, subjects were post-tested to determine their level of attainment/achievement in the topics
covered and to find out the effect of the teaching strategies. All the scripts of the students involved in the study were
marked by the researcher and the records kept for the purpose of data analysis.