Hi August,
That is a bummer that you cannot use a Facebook group as a way to engage your fosters as that usually is a great way to do so. However, another option that you could try would be Doobert's FosterSpace module. Within it, you could invite all of your fosters to join, assign animal profiles to them, and then keep them engaged by sending out Mass Announcements. Those announcements could be foster-specific (dog fosters/cat fosters/etc.) or you could do just as you mentioned, send photos and stories about animals needing a foster or how they are doing, or create polls to gather some further interest, etc.
Hopefully, this helps!
I've also included one of their videos that specifically highlights their announcements topic.
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Kimberly Ruiz
Project Coordinator
Doobert
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