The aim of the present study was to investigate the impact of an educational programme involving peer tutoring at school and family tutoring at home on child reading comprehension achievement in Catalunya, Spain. We drew upon a sample of 303 primary school students from 8 to 11 years old and 223 family tutors from home (61.5% mothers, 15% fathers, 17% both parents, 6.5% siblings). Reading comprehension performance was assessed through standardised tests in pre and post-test bases. Background variables were collected by means of student and parent questionnaires and also teacher and family interviews. An analysis of the family tutoring interactions was also performed. The main results showed positive effects for all the students, but especially for the 223 students who received family support. Overall, the study reveals the effectiveness of peer learning to improve reading comprehension skills and the potential of family involvement for the development of academic skills when the school provides trust and support for it.