DrRacket is a bigger deal to Racket than IDLE is to Python. Specifically because it provides a graphics capable REPL, which is used by a lot of the pedagogical languages and intro to programming courses that racket is perhaps best known for.

(Personally I use xrepl instead, mostly because I don't like DrRacket's text editing. https://docs.racket-lang.org/xrepl/index.html)