I used to have a huge, huge, huge collection of these books! I don't know where they went now, and the only one I can find is "Jessi's Baby-Sitter" (the one when the mean Ramsey aunt moves in and won't let Jessi do anything, including taking baby-sitting jobs AND going to BSC meetings (Mean Auntie actually told Jessi that she couldn't go to the meeting because she didn't know who Claudia is!!!!!) I also have one of the videos (it has a pink case and Claudia is the main character in it).
I wish I could find the rest of my collection. I loved the Super Specials, especially the one where they went to Vermont and the one where they went to New York. I also owned a few of the mystery series spin-offs. I read BSC until I was about 12 1/2 and even owned the special book about Logan!
ETA: I met Ann M Martin when I was about 11 years old and she signed my Super Special 4 (the one where they were lost on the island)!!
My copy of "Jessi's Baby-Sitter" is also signed, but it was to my cousin, who never took it home with her.