She is 'racing against the clock' to be sure the assignment is handed in on time.
Her mind was 'racing'. [=she had many thoughts going quickly through her mind]
Researchers are 'racing (against time)' to find a cure.
(..) Is much higher than anywhere else in our galaxy. And that is absolutely the signpost of the black hole. Narrator: They look like tiny planets racing around an invisible sun. But they're not planets. They're stars. It takes a lot of gravity To swing huge stars around in such fast, tight orbits. (..)2010 TvShow: How the Universe Works Title: Black Holes Season: 1 Episode 2