Tom Bober , these collections of primary sources that go with picture books that you're doing are such a great resources!  I especially appreciate the short text.  I've previously mentioned another TPS source for coordinating with literature - the TPS-Waynesburg University site Book Backdrops.   I've been using the site for several years, and notice that the URL frequently changes. 

The concept of Book Backdrops is a good fit across several groups here in the TPS Teachers Network:

• Primary Sources in the School Library
• Bookmarks!
• Primary Sources in Elementary Education
• See, Think, Wonder: Primary Sources in Early Childhood

I have two suggestions for making Book Backdrop posts easier to find:

1. Let's try to get into the habit of adding the tag  Book Backdrops to every post that ties picture books and primary sources together. You will see that I added the tag to  Tom Bober 's album as an example. 
2. We now have an option to post across groups. Whenever a user posts a discussion, a link, a file, or an album that matches primary sources with books, that user can navigate to another group and attach the previously submitted content to a new post. It's an added attachment bonus you'll find right under the text box whenever you post something, and it even includes a search option so you can find your previous post title and select it. I haven't tested this new feature yet, but anyone is welcome to try it. I believe you can attach any of your own materials from the group you're currently in or from any public groups.

In sum, the easiest way to facilitate finding more Book Backdrops is to add tags to your posts. The more challenging way is to post across multiple groups, but again, always use the tag  Book Backdrops .

Finally, if you cannot access Book Backdrops in other groups, you may need (and want) to join them!