For teachers, an auto-grading quiz in Google Forms is a really easy way to save some time. On your main Google Forms page, click Template gallery at the top. Scroll down and under Education, pick Blank Quiz.
Click Add Question from the toolbar, enter the question, and click Answer Key to provide the correct answer and point value for the question. When your respondents finish the quiz, they will see an option to View Score. This shows them all questions answered, marked as correct or incorrect, and the points they received.