Ngl i still think this was just panda trying to make kyo and yamada an offical couple, but she doesn't know that they are already dating. Remember she tried to make the offical couple celebration with them on the school trip, but it didn't work out, I don't think she forget, she just didn't attempt it again till now. And knowing her character, Im guessing she would have thought that the perfect gift to yamada would be to get kyo to confess to her and them be a couple, but she doesn't know that they already are one. Just a theory, knowing Norio-sensei, it could be anything.