The aim of the study is to investigate whether the activity based posters have an effect of on the ninth class students' academic achievements and the retention levels in their learning. The research was carried out with 60 students at one of the state schools in The Central Anatolia Region of Turkey in 2015-2016 academic year. Study--"Celebrities" unit teaching--took 6 weeks in both experimental group and control group. This study was conducted according to the "pre-test-post-test control group model" which is from quantitative research methods. The unit of "Celebrities" Achievement Test was developed by the researcher. These data collection tools were implemented at the beginning and the end of the study. Academic Achievement Test was re-implemented 21 days later after study in order to determine the retention levels in their learning. At the end of the research, it is detected that implementation of the activity based posters in English classes makes statistically significant difference for the benefit of experimental groups on the level of academic success.