Our hands-on hardwood blocks make it easy for children to count and visualize quantities to 10! Each roof block features a numeral from 1 to 10 on one side and the corresponding number word on the other. Kids select a roof, find 2 base pieces with quantities of windows that add up to the target number…and place the roof right on top! You get a set of 42 blocks; roofs measure 3 1⁄2".