This app was mentioned in 2 comments, with an average of 1.00 upvote
You can have text memos on your "desktop", which seems like a half-solution, but could be faster than switching between apps: https://play.google.com/store/apps/details?id=jp.miotti.TextMemoWidget
Text Memo Widget - Do I need to buy something after school? Put it right on the homescreen!