survey monkey classroom assessment

This week, I created a classroom assessment by use of Survey Monkey.  I found it very easy to use and put together.  A general concern is that since it is not through LMS, anyone could potentially take the survey and skew classroom results, or a student can even take the survey multiple times to skew results. But using it as classroom assessment really gives me the opportunity to improve my classes, and students will get the feeling that their opinions matter which helps build a better report among students.
This is a survey I created for my classes https://www.surveymonkey.com/r/LWMYFNK