The formula is:
=image("https://chart.googleapis.com/chart?chs=150x150&cht=qr&chl=" & B2)(when the information you what the QR code to disclose is in cell B2). Don't have the information in cell B2? You can change the formula to look to any cell you want!
Need more information than just access to the formula? Watch this brief video that walks you through the entire process that Jeanette used! I think you'll find using Google spreadsheets to generate your QR codes a real time saver!