The study investigated Effect of Assessment for Learning (AFL) on Biology Academic Achievement of Senior Secondary Students in Rivers State. The researchers adopted a non-randomized pretest-posttest control group quasi-experimental research design. The population of the study consists of 34,825, Senior Secondary Two (SS2) students duly registered in public secondary schools (2013/2014 Session) in the 23 Local Government Areas of Rivers State, Nigeria. A total of 400 Senior Secondary Two (SS2) students’ (200 males and females respectively) were sampled through multistage sampling technique in Ikwerre, Obio/Akpor, Ogu/Bolo, Okrika and Port Harcourt Local Government Areas. Students’ in intact classes were assigned to four experimental groups and one control group. Students’ in the experimental groups were subjected to the following Assessment For Learning strategies: use of questioning, comment only marking, self/peer assessment and formative use of summative assessment, while students’ in the control group were subjected to the traditional assessment method. Two research questions and two hypotheses were postulated for the study. A 40 item instrument titled: “Assessment For Learning Biology Achievement Test” (AFLBAT) developed by the researchers was used for data collection. The instrument was duly validated by three subject specialists and two experts in educational measurement and evaluation. An internal consistency coefficient of 0.71 was obtained using Rulon formula. Data for the study were analyzed using descriptive statistics (mean, and standard deviation), analysis of covariance (ANCOVA) and paired sample t-test. The analysis of data was done using SPSS software. The result of the study revealed that: Assessment For Learning strategies effectively improved biology achievement of students’; biology academic achievement of students was enhanced by the following AFL strategies: use of questioning, comment only marking and self/peer assessment but the most effective is comment only marking; AFL has a significant effect on biology academic achievement of students. Based on the results of the study, the following recommendation among others was made by the researchers: a critical review of classroom assessment methods is advocated, especially in the aspect of comments made by teachers concerning learning outcome of students’.
Keywords: Academic Achievement, Assessment for Learning, Biology, Formative assessment, Summative Assessment