The cute gorilla is by Lionel Albertino, you can find it in “Safari Origami”, ISBN 2844240062. You can download the book because the author re-published it for free, thanks to him! It’s in French, but folding conventions are international :)The book has plenty of other models.
It’s folded from one sheet of square 20cm paper. I really like the mouth :)
The leaves are by Jeremy Shafer. They’re folded from one square sheet of 20cm paper. Here’s the video tutorial.
Jeremy Shafer published a youtube tutorial for this flapping butterfly card. Paper: 35 cm double-sided paper from origami-shop.com (don’t try smaller paper on your first try). And yes, the butterfly does flap its wings when you pull on the sides of the card :)
The skeleton hand is found in this video tutorial. Paper: 15 cm kami. People like this model a lot, it’s especially popular around Halloween :)
Both models are high-intermediary. They’re not in his books, but he has many other amusing models to fold :)
These adorable bats are very, very popular among all the people I give my origami to. I fold them regularly, because I know people will always be happy to have one – I think it’s partly because of the magic of pop-ups, but they’re also particularly beautiful.
The bat on the right is folded with 24cm double-sided paper. The bat in the middle is from Tuttle Rainbow patterns 15cm. I don’t remember the leftmost paper.
You can find the (beautifully hand-drawned) diagram in “Origami Pop-Ups to Amuse and Amaze” (ISBN 978-1494299026). He also made a youtube video.