Field that stores multiple checkbox values
I'm trying to get a text field to store multiple values from one checkbox value list into one record. I have one global field named grade_years, and a value list that includes 6, 7, 8... and so on until 12th grade. I would like to be able to select multiple grades (such as 8,9 and 10) and have the global field grade_years display as : 8 9 10. I know it's probably pretty easy to do with a calculation field, I just haven't been able to figure out how to do it. Any help would be appreciated, thanks.