O2Jam is a popular online game that focuses on music – rhythm,to be more exact. So, if you want a non-violent game that you and your children can enjoy for free, this is one of the best choices.
All you have to do is find a room (also known as a channel) to play in, and then select and play a song. You can choose from 580 official songs (there are also over 700 unofficial ones).
Each channel can accommodate up to a maximum of 100 online users. There are also various types of channels: Album, Single, VS and Couple rooms. To play the song, you must press the key that corresponds to the column that contains the correct note. Notes slide down on 7 columns and you can get a Cool, a Good, a Bad or a Miss grade, depending on how accurate you are.
O2Jam requires few resources to run and takes up just around 430MB of disk space. However, most of the songs are not included in the initial download.