One thing I really like about noredink is that you can personalize your account. You enter some interest preferences and some information related to you when you "Update Interests" in "Preferences." Then when you work on assignments and quizzes, the site will tap into your account interest preferences to fill out sentences. Trust me, it's worth the little bit of time.
Below is a video by another teacher telling her class how to personalize preferences. Follow her directions but ignore her course code unless you want to join some 9th grade class at East Ihavenoidea High School.