Here is a site for your students to try. It is called Webonauts. This site comes from PBS Kids. Its purpose it to teach students about Internet Safety and about being a responsible citizen. Here what PBS says about Webonauts:
"Webonauts Internet Academy is a web original game from PBS KIDS GO! that gives kids 8 to 10 years old an opportunity to have some fun while exploring what it means to be a citizen in a web-infused, information-rich world. It is an engaging experience on its own but becomes all the more powerful when parents and teachers use game play as a springboard for conversations about media literacy and citizenship in the 21st Century."
Our students explored this site and really found it engaging. Students have to problem solve and make good choices in order to work their way through the Webonauts Academy. We had our student make a username and password so that they could stop and continue Webonauts when we had time. We first discussed safe ways to make a username and password before they started. All usernames and passwords had to be approved by the teacher and written down on a sticky label attached to their planners.
I would try Webonauts yourself before using it with your students.