I have created a sign in/out sheet for students within my building. Students will type their name in column A, click a checkbox as a timestamp when leaving and entering and a dropdown for where they are going. The information for each class is then sent back to another sheet where I process the information and gain data on each individual student's habits using a query function. I have utilized a few scripts for the timestamp and for overwrite protection to protect students from altering previous student information. My next goal is to have the students type their name and then generate a popup window asking for a password (specifically a lunch code that is unique to each student) to keep students from leaving their rooms under the guise of another student's information. Does anyone have an idea of how I could create such a thing? In the sheet that I am attaching the student names are located in tab labeled StudentRoster, in the roster column A has their name, and column B has their lunch code. In my mind I would like the student to select/type their name in the Sign In/Out tab in column A and generate a pop window to ask for their lunch code and to only proceed if the lunch code matches what is found in column B of StudentRoster tab. If this is not possible I am willing to hear suggestions/ideas for figuring something like this out.