
Choice Eliminator is a Google Forms Add-on that lets you create a Form on which choices disappear after they have been used. For example, if I create a Google Form that has ten meeting times listed on it, once a meeting time has been selected it will disappear from the options available to subsequent visitors. Using Choice Eliminator is a good option for teachers who have personal Google Accounts, but don't have G Suite for Education accounts. Of course, it works well if you do have a G Suite for Education account. There are two versions of Choice Eliminator. The "lite" version is recommended for Forms that will be shared with a limited audience. The "2" version is recommended for use with larger audiences.
formRecycler is a free Google Forms Add-on that makes it easy to reuse questions from one Google Form into another form. When you have the formRecycler Add-on installed you can access all of your existing Google Forms and then pick questions from one of those existing Forms to use in a new form. You can use formRecycler multiple times on the same form and thereby include questions from multiple existing forms in your new form.
FormLimiter allows you to set a time for a form to automatically stop accepting responses. You can also use FormLimiter to set a limit on number of responses a form will accept. Watch my video to learn how to enable and set limits on Google Forms.
If you missed my post on Saturday, here's a video about the CheckItOut Google Forms Add-on.
An add-on that I started using in January and absolutely love is Certify'em. You can use this add-on to automatically issue certificates to students when they successfully pass a quiz.