Understanding place value concepts is easier than ever—with our innovative number hunt! Children simply place a number finder on top of any number on the chart…then slide open the doors to find 1 more, 1 less, 10 more and 10 less! Great for independent practice or small-group instruction, our skill-building set comes with 4 chipboard number finders, each with 4 slide-open doors, plus 4 copies of a chart printed with numbers 1-100. Charts measure 13 1/4" x 15".