These puzzles - the Pups in Cups - are a huge hit at the library where I work. We've also got the mini-puzzles of the reef fish and the birds, and they all have been a huge hit - I spread all the pieces out on a low bookshelf, and usually will find the pieces sorted for the individual puzzles within a very short time. And once that's done, throughout the days (and nights) we'll see students taking a break from studying to stop and spend a few minutes working one or two of the mini-puzzles. All of the puzzles - but the pups in cups especially - are colorful, and fun, and while not huge, somewhat challenging - at least, enough for someone to clear their head and get a good study break. We all just love these (yes, I use them for work breaks too!)