If the game freezes, just click inside it (games can get unresponsive if you click elsewhere on the page).
In this game you play the note that appears on the staff. At first the notes will be simple notes that spans only one ocatve with no sharps and flats, as the game progresses more difficult notes will be presented and the frequency of appearance of the notes will also increase. You can test your fluency with musical notes in this game.
This game is played by mouse only.