well, my class just finished studying Sumer and Sumerians. Sumerians developed alot of things. they developed cuneiform which was the world’s first system of writing using pictographs and symbols. They also developed the wheel which they used for pottery (potters wheel) and they developed medicines and in math, they developed a system revolving around the number 60. For example, there are 60 seconds in a minute and 60 minutes in an hour and yeah. Oh and the plow, used for farming which increased farm and food production. Thats all i can remember, but in my opinion, the most impressive is the writing development.