Any idea you like is a good idea - if you want an assignment, your teacher is the best one to give you one! That's what you're doing when you ask someone else to tell you what to write. Here's a good link to show you where authors get ideas.
Well... good animal stories ideas are a rabbit fighting a kangaroo!
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I'm not a real author, but I do enjoy writing stories, especially about animals. It's probably a bit late now, but anyone else looking at this can have them..... I'm not sure whether you want the story to be from a humans or an animal's point of view, so I'm just going to list everything.
-A species of animal form a group to not have to live with humans/in zoos anymore.
-A natural disaster causes all the humans to evacuate, leaving their beloved pets behind. Do they return, or do the pets have to learn to survive in an unforgiving city?
-Your calm, uncaring pet over there is actually a shapeshifter from another planet....
-Scientists form a new species of (animal), perfect for keeping as a pet, but little do they realize these new animals are intelligent.
-At an animal testing facility, a cat has been given a new type of hair product. It gives the cat human-like intelligence, and it soon escapes, ready to take revenge on humankind.
-Every time the animal touches water, it grows slightly bigger.
-A dog digs it's way under the backyard fence, only to fall into an underground system of tunnels, all used by a tribe of dogs.
-A dog goes with his family camping, but they lose him in the forest. What troubles does he have to go through to get back home?
-An (animal) is struck by lightning, but survives. It seems to be acting very odd now though....
-A dog's point of view on a trip to the vet.
-Diary of a dog. Make it is as simple or detailed as you like. For a simple one, best for Children's Books, it could just be.....Woke up. Scratched. Looked for food. Saw dry biscuits. Ate human's cake instead. Slept etc.
Well, here's 9 or 10 ideas, I can't be stuffed counting, I hope this gives any readers a bit of inspiration.
Here are some good links
You'll have to learn how to come up with your own story ideas if you want to write anime! Try THIS link to see how writers get their ideas.
Anything that you have survived is a good survival story. If you want to write a general story about wilderness survival, anything you are willing to research enough to write will be a good story. You have to be interested enough in something to come up with your own ideas, otherwise it's not going to be a good story.
Write a story about a fictitious person. It worked for me
It depends what kind of story. If it is a fantasy story, then perhaps a talking squirrel or other small creature. If it is some kind of adventure story, and this animal is a companion, something a tad larger, a deer maybe?
If you're in the planning stage, you should brainstorm for ideas and then make an outline.
A story in which ideas are symbolized as people is called an allegory. In an allegory, characters and events represent abstract ideas or moral qualities, often serving as a way to convey a moral or political message. Examples of allegorical stories include "Animal Farm" by George Orwell and "The Pilgrim's Progress" by John Bunyan.
Some examples of big ideas in a story could include themes such as love conquering all, the struggle between good and evil, the quest for identity or self-discovery, and the impact of technology on society. These big ideas often serve as central themes that drive the plot and character development in a story.
Over the hedge, Madagascar, GForce, Horton hears a who
There is loads you can do about animals, for example; Evolution. Animal behavior. Stem cell research
This depends on what you think is a good treasure! You're the writer, not some anonymous person on the internet -- here's a link to show you how authors get story ideas on their own.
I'm no author or anything, but I do think these are some good ideas for your story. Head Over Heels Teenage Attraction Teenage love The Trip of a Lifetime A Lovers Vacation note: these are just a few ideas for your story.