How can I make an exam with 12 questions but only require students to choose 10 questions for full points?
This functionality is not supported directly, so you'll need to use a creative approach.
The approach depends on the type of questions.
If the questions are essay questions and they are supposed to pick 10 of the 12 to answer, then you could make a text-only question that listed the 12 questions, then provide 10 essay questions for them to provide their responses. Make the instructions clear that they must identify they question that they are answering as part of each response. When you go to grade them, pay extra close attention to make sure they didn't answer the same question more than once for each student (this can be difficult to pick up on if you're grading a question at a time). See Students choose which questions to answer on Quiz for an example.
A second approach works for any type of question, including essay questions, and allows you to randomize the order of them. Go ahead and make the 12 questions and make it perfectly clear to the students that they should only answer 10 of them and what will happen if they answer more than 10 (will you drop the two worst questions, only grade the first 10, grade all of them with the option of extra credit, etc. ?) This should be made clear both in the quiz and any supplemental information you provide them ahead of time (in-class explanation, study guide, etc.). At the end of the quiz, you'll have to go through each quiz manually (I'd use SpeedGrader) and use the fudge points to adjust the total.
This question comes up periodically and has been the basis for several feature ideas. Many of them have ended up with few votes and relegated to cold storage, but there is still one idea that is currently open. You may want to go there and lend your support: Question Choices in Quiz
Thanks James! Doable workarounds but I did vote for the currently open variety.
Retrieving data ...