Start by reading the problem to the children. Let them work individually or in small groups to solve it. If the answer requires writing, encourage them to use “kindergarten” (phonetic) spelling. It may not be pretty (or even decipherable) at this point in the year, so expect to go around and do a lot of dictation. It is more important, right now, for kids to be able to talk (than write) about their solutions.
When most of the children have completed their solutions, bring them to Mathematician's Chair to share/discuss their answers. (See tips here.)
You will be amazed with the variety of answers kids will come up with for this question. Of course, there is The fish--because it lives in the water. But then again, it might be The cat--because it can't swim. Or The fish--because it doesn't have legs. Or The cat--because the dog will chase the cat and the cat will eat the fish, but the dog and the fish will get along just fine!
Seems simple--3 tails, 3 cats, right? But wait--maybe it's 10 cats, but only 3 are sticking out their tails. Or maybe its Zero cats--there are puppies in the box. Here's a great question for Mathematician's Chair: Can there be just 2 cats in the box?
Is it a dog? Cat? Elephant?