Meeting workspaces, site templates designed specially for meetings, have been discontinued in SharePoint 2013. However they sill exist and can be reactivated. Navigate to the site templates in the “15” hive (C:\Program Files\Common Files\microsoft shared\Web Server Extensions\15\TEMPLATE\1033\XML). Edit the webtemp.xml, scroll to the MPS templates and set the Hidden attribute to FALSE on the configuration tags.
If you now want to create a new sub web you can select one of the meeting workspaces, however a SharePoint calendar event still won’t allow you to connect it to a meeting workspace. If you use our SharePoint Employee Training Management or the SharePoint Calendar E-Mail Extension you will however be able to do this.
Update: In the following post I describe an approach how to enable meeting workspaces in SharePoint 2013 without changing the webtemp file in the SharePoint 15 HIVE.
Enable Meeting Workspaces in SharePoint 2013