Gradekeeper and FERPA
The Family Educational Rights and Privacy Act (FERPA) is intended to protect the privacy of student educational records. Using Gradekeeper's export to web capability does not violate FERPA so long as you take proper precautions. The key is that you cannot disclose a student's grades to anyone other than the student and their parents (if they are under 18).
Export to Web - Single Page
When you choose to create a single web page, you are creating a web page that anyone can see. Student names are not included, but student IDs are. You cannot use social security numbers (even just the last 4 digits) or any other easily obtained number. Do not use phone numbers, locker numbers, or book numbers as student IDs. The best option is to use randomly generated numbers for IDs and to sort by ID before exporting to web.
Export to Web - Web Site
When you choose to create a web site, the student grades are only available when a valid student name and ID are entered. But, if someone should gain access to a student's grades, due to an improperly configured server or an easily guessed ID, your school can still be liable. The best option is to use randomly generated numbers as IDs.
Do not enable directory listing, as this will make it possible to get a list of all student web pages and choose any of them. Do not enable sever statistics on your web server, as this may create a web page with links to frequently accessed web pages, including student web pages. Do not change or remove the robots.txt file. This file tells search engines not to index the contents of your grades folder.
I also recommend against including student names when creating a web site. While many people prefer to see their name to be sure that they are seeing their own grades, this also means that anyone who does access a student web page will know whose grades they are seeing.
Posting grades online is not the only area you should be concerned about. If students have access to classes on your computer, this would also violate FERPA. You should insure that your computer is secure or at least create a password for each class. If you need to show a student their grades, use the student scores report so they can only see their grades.