Passive and active visuospatial working memory (VSWM) were investigated in relation to maths performance. The mental rotation task was employed as a measure of active VSWM whereas passive VSWM was investigated using a modified Corsi Blocks task and a matrix pattern task. The Raven Progressive Matrices Test measured fluid intelligence. A total of 128 students, aged 15-16, served as participants. Fluid intelligence and passive VSWM accounted for variance in overall maths performance. Active VSWM exhibited significant correlations with maths measures, but in a series of regression analyses most of its effect was observed to be mediated by fluid intelligence. Different subscores of mathematical skills (geometry, word problems, and mental arithmetic) were accounted for by fluid intelligence and different measure s of VSWM. The educational implications of the results are discussed. (Contains 5 figures and 3 tables.)