Tthe Objectives are:(1) To study the self- instructional methods viz., programmed instructional method (PIM) as a reinforcement strategy and its effect on learning the topic Genetics’ among the students of higher secondary school. (2) To develop and evaluate the programmed instructional packages (PIM) and computer instructional packages (CAIM) on Genetics’ for teaching the standard XII students selected for the study. (3) To develop tools to measure the effectiveness of self - instructional packages on Genetics’ through programmed instructional packages (PIM) and computer instructional packages (CAIM). (4) To study and compare the effectiveness of self- instructional methods and materials i.e. PIM and CAIM as a reinforcement strategy on achievement and retention of cognitive skills in Genetics’ such as knowledge, understanding and application among the students selected for the study. (5) To study the effect of intervening variables on achievement and retention in cognitive skills in Genetics’ among the higher secondary school students selected for the study.

The study had following hypothesis: (1) There will be a significant mean score difference in cognitive skills in Genetics between test -2 and test -1 (Achievement - I) due to conventional teaching method among the selected students of the control group and experimental group. (2) There will be a significant mean score difference in cognitive skills in Genetics between Achievement – I (T2- T1) and Achievement – 2 (T3- T1) due to conventional teaching method among the selected students of the experimental group. (3) There will be a significant mean score difference in cognitive skills in Genetics in Achievement – I between the control group and experimental group. (4) There will be a significant mean score difference in cognitive skills in Genetics in retention – 2 between the control group and experimental group. (5) There will be a significant relationship between Achievement (1 & 2) and intervening variables such as socio – economic status, language abilities, reasoning ability, exposure to mass- media, exposure to science programs, study habits and interests in co- curricular activities among the students of the control, PIM and CAIM groups of the study. (6) There will be a significant relationship between retention (T1 & T2) and intervening variables, such as, socio – economic status, language abilities, reasoning ability, exposure to mass media, exposure to science programs, study habits and interests in co- curricular activities among the students of the control, PIM and CAIM groups of the study.

A total of 178 students (boys and girls) from various higher secondary schools were selected as sample.

The tools of measures were: CAI: Software evaluation Performa; Performa to collect personal information data; Criterion referenced test (CRT); Test of abstract reasoning (adapted from DAT); Test of language usage (Adapted from DAT).

Quasi- experimental, within and between group design was used.

The study arrived at following findings; (1) The students in the control group and experimental groups are able to retain significant amount of knowledge on Genetics obtained through the conventional method of teaching. Further the retention – 1 in all the groups of the study are more or less similar. (2) The reinforcement strategy employed in the study is effective in terms of achievement in cognitive skills in Genetics. (3) The PIM and CAIM employed in the study facilitated effectively retention of cognitive skills in Genetics. (4) Reinforcement has facilitated the increase in retention of cognitive skills in the experimental group. (5) Conventional method of teaching is equally effective in acquiring cognitive skills in Genetics in all the three groups. (6) Both the reinforcement strategies are equally effective in learning and retaining the same in the experimental groups. (7) The selected intervening variables do not influence the achievements in cognitive skills in genetics among the students of the study. (8) The intervening variables such as socio – economic status, language usage, arithmetic reasoning, exposure to science programs, reading habits and participation in co – curricular activities do not influence retention (S) in cognitive skills in Genetics among the students in the control and experimental groups. (9) Sex did not influence the achievements (A1 & A2) and retentions (R1 & R2) in cognitive skills on Genetics among the students of the control and experimental groups.