The interactive sheet music for the recorder contained in this site allow you to play with the accompaniment of the computer. You can modify the speed of the playback if you want it.
When you start learning a new song, it can be useful to study it slower and then to increase the speed progressively.
In order to change the tempo, you must load the scores from Noteflight, the web application used to edit them. You can do it with a clic in the button at the top left corner of the score, highlighted in red in the picture below.
In the new window, you can change the tempo with the cursor highlighted with the red rectangle in the following image.
