This activity is a great way to introduce conversion factors to students - and feed them a little history too! On this worksheet students are given data about the Roman army during the 1st and 2nd Punic Wars. They are asked questions requiring conversions. Students use the conversion cards to cross cancel units and get to the answer. The Roman army is a great platform because they used clear and defined units. Plus, students are fascinated with Roman history. This activity comes with a key and cut-outs. Enjoy!