Metric Rod Series are effective tools for physically representing various math concepts. Not only do they demonstrate numerical, place and equivalent values; but also teach simple math calculations. With hands-on practice, the child can learn the relationship between units, tens, hundreds and thousands. As each unit is 1 cm on all sides, children can also practice measuring and calculating length, area and volume. Marked Metric Rod Set and Series contain weights that are equivalent to the length, and can be used as weights with a balance. The markings on the rod also allow the child to visualize many math concepts more easily. Plain Metric Rod Set lunweighted) strengthens the child's observational skills by allowing the child to practice ruler measurement and visual estimation.