Pictured above is Provo, Utah's Meghan Hunter, who improved 3.09 seconds.
We used our database to find out which girls improved the most in the hurdles from 2017 to 2018.
The most improved girl in the 300mH was Melissa Symons from Lake Orion high school in Michigan. Symons went from running 46.36 in 2017 to 43.02 in 2018 for a little over a three-second improvement. She was only a junior this season, so we will see how much more she can improve come next spring.
Take a look at the full 300mH and 400mH year-over-year improvement rankings in the links below.