Top: Kids and Teens: School Time: Science: Units of Measurement (3)
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Convert-me.Com - Interactive calculators for many common and exotic measurement systems, including metric, Ancient Greek, Roman, and old Russian.

CyberSleuth: Units of Measurements Worksheets - Twenty-three printable worksheets for elementary school-aged children. Focuses primarily on conversion of units of length.

Measurement Worksheets - Features printable worksheets. Includes English and Metric System pages.