The Openings report provides you with a list of classes that display your classes that have openings. In addition, there is a % Full column that displays a graphic representation of how full your classes are. This report can be found under the Reports (menu) > Find Reports > Classes/Enrollment (left menu) > Classes (tab) and click Openings.
Some of the columns contain clickable links that open additional information.
Save this as a frequently used report! Click the heart (icon)next to a report name, the heart will change to redand the report will be listed under the Reports (menu) > My Reports for quick and easy access!