The current study investigated whether a domain-specific intervention of ExeFun-Mat targeting math and executive functions in primary school children with a Roma background would be effective in improving their scholastic performance and executive functioning. ExeFun-Mat is based on the principles of the reciprocal teaching approach, scaffolding and self-questioning. The domain-specific content was divided into modules. Each module consisted of a set of graded tasks. The criteria for the grading and hierarchical organization of the tasks were based on the level of cognitive difficulty and the type of representation. In total, 122 students attending grade four of elementary school took part in the project. The study concerned a pretest-intervention-posttest experimental design with three conditions: the experimental condition, an active, and a passive control group. To assess the children's level of EF, the Delis-Kaplan executive function system test battery was used; to assess children's mathematical achievement, the cognitive abilities test (the numeracy battery), and ZAREKI--a neuropsychological test battery for numerical processing and calculation--were used. The results suggested that both math performance and executive functions improved over time, with no significant differences between the three conditions. An additional correlational analysis indicated that pretest performance was not related to posttest performance for the children in the experimental and active control group.