Reading individual notes is a incremental building block that can later be used for sight reading music. These games make sight reading fun to learn and competitive:
- Reading on the Treble or Bass Clef (has 10 levels and has a score)- http://www.vicfirth.com/education/keyboard/speednotegame.php
- Reading on the Treble or Bass Clef (has 3 levels and has a score) - http://www.teachingideas.co.uk/music/namethatnote.htm
Bonus:
Sight reading series - I Can Read Music: A Note Reading Book for Violin Students by Joanne Martin - this series is available for the treble staff. Wish they had one for bass! Although it says it is "for Violin" Students, it can easily be used for voice practice.