Word for sandbox/journal/scrapbook/testing area, related to writing

single-word-requests

I know the word exists, I can't remember what the word is, but it means "area for rough work", and is related to pen and paper notes.

I.e. "I took notes on/in my __."


I suggest

scratch pad
NOUN

1 A notepad.

He also keeps on that clipboard a scratch pad where he jots down ideas for a screenplay he's developing (he wouldn't share the details) and verses for his hobby as a spoken-word poet.

From Lexico.

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