Quality of fathers’ spatial concept support during block building predicts their daughters’ early math skills – But not their sons’

•Ratings of father–child video interactions assessed fathers’ spatial support.•Fathers’ higher quality of spatial concept support predicted higher math scores only for girls.•Controlled for covariates including father/mother general cognitive stimulation.•1st graders’ independent accuracy on block building task predicted their math.•Correlational but findings suggest importance of family spatial concept support for girls.