This study aimed at investigating the effectiveness of planned focus on form method in the acquisition of target language forms in English. The study specifically examined the planned focus on form method and the teaching model in the textbook of the 5th graders in terms of the attainment of the objectives of the target unit 'Health'. The participants of the study were 5th grade learners (n= 60) studying at a state secondary school in Milas in the district of Mugla province in Turkey. The research was a quasi-experimental research design in which two intact 5th grade classes were assigned as experimental and control groups. The data collected from pre-test, progress achievement tests, and the post-test were analysed using the SPSS 17.0 statistical programme. The progress achievement test scores and post-test scores of the subjects were analysed through independent samples t-test in order to analyse which instructional treatment was more effective in reaching the objectives of the unit. Repeated measures ANOVA test was also administered in order to measure the effects of the treatment in time, which indicated that both treatment types were effective in increasing the learners' scores from pre-test to post-test. The statistical analysis of data indicated that planned focus on form was significantly more effective than the regular instruction according to the results of the progress achievement tests [t(58)= 2.67; p=0.010]. The results of the post-test did not indicate a statistically significant difference between the two groups [t(58)= -1.058: p= 0.294], the experimental group (M=60.86) performed better than the control group (M=55.06) in the post-test, though.