This quantitative–qualitative study determined the relationship of attitude, truancy and achievement in science of grade 7 students in public sub-urban school. Specifically, it sought to find the relationship between attitude, truancy and achievement of the grade 7 students as a whole and when grouped according to sex. A science attitude questionnaire was administered to 122 students in grade 7. Their attendance and second quarter grade were collected. Mean and standard deviation were used as descriptive analysis. The Pearsons? r was used to ascertain if there is significant relationship between attitude and achievement and between truancy and achievement of the grade 7 students. The level of significance was set at 0.05. The qualitative data was taken from two selected participants who were subjected to an interview and self-assessment. Results showed that the grade 7 students in a public sub-urban school has a “high attitude”, considered as “not truant” and classified as “satisfactory” in their achievement. The study also showed that as a whole, there is no significant relationship between the attitude and achievement when categorized according to male. However, there is a significant relationship between attitude and achievement when categorized according to female. On the other hand, the truancy of both male and female grade 7 students in science correlates to their science achievement. The qualitative results showed that the students? attitude relates to their achievement in science through performing experiments, finding alternative ways to catch up and positive results in their activities in the classroom. The researchers concluded that the favorable and unfavorable outlook of students do not matter and do not relate to their achievement but it is a must for them to be present during their class in order to secure and attain a high achievement.