These are three great websites with lots of topics related to our studies of Ancient Mesopotamia:
http://www.historyshistories.com/mesopotamia.html
http://www.ducksters.com/history/mesopotamia/ancient_sumer.php
http://mesopotamia.mrdonn.org/sumer.html
You find a ton links within each of these websites if you want to learn more about topics like; cuneiform, religion, weapons, inventions, Code of Hammurabi, the Epic of Gilgamesh and more!
Games
Here are some games that teach about life in a Sumerian city, or about their ancient artifacts
(These are older games, they won't work on Chrome, but usually will work if you use Firefox or Internet Explorer. Some of these games you may need to “allow pop-ups” in order for the game to work.)
Royal game of Ur
Build a Ziggurat
http://www.mesopotamia.co.uk/ziggurats/challenge/cha_set.html
Farming Game
http://www.mesopotamia.co.uk/geography/challenge/cha_set.html
Write like a Babylonian
http://www.penn.museum/cgi/cuneiform.cgi
Protect yourself from Demons -
http://www.mesopotamia.co.uk/palaces/challenge/cha_set.html
Archaeologist Challenge - Use the book to find what layer each artifact was found in
http://mesopotamia.co.uk/time/challenge/cha_set.html
Ancient Weapons Challenge - match the artifacts found to the weapon it originally came from
http://www.mesopotamia.co.uk/warfare/challenge/cha_set.html
Videos
These are some informational and entertaining videos.
Sumerian City States
http://www.youtube.com/watch?v=4AiPRMp_6Kc
City-States of Ancient Sumer
http://www.youtube.com/watch?v=e3TJsgVYoKw
Mesopotamia - from nomads to farmers
https://www.youtube.com/watch?v=gMMSBfT3FFg
Mesopotamia-Sumeria, First Civilization on Earth
http://www.youtube.com/watch?v=w8v2vRlLL58