Yes. It's not very intuitive, but you can stretch or shrink the clip to alter the speed, then go to that clip's media properties and choose the method. Change length, preserve pitch will alter the tempo without making the pitch higher or lower. This works well for a limited range, but can start to sound very choppy or metalic if you go too far. Change length and pitch will sound more like speeding up or slowing down a tape recording. If you don't mind the pitch change, this can be used for a much wider range of speed change without breaking up the sound. You may manually enter a new length if you want to do the math and set an exact tempo.