On Monday Google Forms received an update that allows you to create automatically graded multiple choice and true/false quizzes. To do this just go into your Form's settings menu and select "quizzes." You can then specify point values for each multiple choice question in your Form. In that same menu you can enter answer explanations. The quizzes setting also gives you the option of letting students see their scores immediately after completing a quiz. The quizzes setting is convenient, but it is not as feature-laden as the Google Sheets Add-on called Flubaroo.
Via CM Elias, Jim Lerman