The third grade Navigate students have been busy exploring ancient number systems. They have learned to write in Egyptian and Roman Numerals. Both of these systems had their positives and negatives. The students found that Egyptians had a number system in base ten so it was easier to understand, but writing out numbers proved to be time consuming. During our discussions on Roman Numerals, the students realized that they needed to be very quick at mental math in order to figure out the values of the numbers. We discussed expanded form as well as the similarities and differences of our Hindu Arabic number system!