Flippity.net is a free online resource that will easily turn Google Spreadsheets into a set of online flashcards, or an online Jeopardy game.
Once you complete the steps to create your online content, it becomes dynamic in nature. As you change the contents of the spreadsheet, including adding or removing rows, the online flashcards or gameboard also changes.
This enables a teacher to maintain one Google Spreadsheet, and then use the same link they have bookmarked for flashcard review or a Jeopardy game. This link can be a QR code on a wall, or simply bookmarked for easy access.
Have students create their own sets of online flashcards or Jeopardy game boards, and share with each their peers.