I've just released the OG Group Content module https://www.drupal.org/project/og_groupcontent on drupal.org. Here is the description of the module from drupal.org:
"The OG Group Content module creates all the basic popular content types often used in a group setting, blogs, wikis, events, polls, announcements and creates with very little configuration a nice looking framework for your organic groups. There are even special types of blogs for instructors, and there is a syllabi content type available. There is also a nice calendar which displays events or syllabi if those content types are used. If you don't want to use a content type, not a problem, you can pick and choose which ones you want to use on the site."