A Fairy Tale

When do you use "further" and when do you use "farther"? That is my question, friends.
I had to write a fairy tale as part of my children's lit midterm (other parts of the midterm include analyzing my own fairy tale....gross). I had to make sure there were some cultural and/or social values included, and I also had to choose 5-7 elements from a list and incorporate them. I chose the prince, the sea, a talking fish, a lion, a golden ball, and a sword. I also had to do it in 2 double-spaced pages, which was DEFINITELY the hardest part of the whole assignment.
Here it is, and my apologies for its utter lameness, clicheness, and overall hoity toity tone. I haven't done a hoity toity in years; it was kinda fun.

Once upon a time there was a prince who lived in a castle by the sea. His father the king ruled over his people, the Marans, who all had a great love of ships and seafaring. The prince, too, loved ships, and when he was fifteen years old he began to build himself a seaworthy boat. When he was 20, it was finished: a beautiful light ship, fast and sturdy. He named it the Spearfish. Obtaining leave from his father, the prince sailed off on his first sea-voyage alone. He had decided he would not return home until he found something of value, or something to prove that he was worthy of being the king’s heir.
His voyage started smoothly. He visited several nearby islands, and then ventured far away from the mainland, farther than he had ever gone before. After many days he had nearly depleted all of his food. The prince tried to catch a fish to feed himself, and at last caught one. It was very large. The sun sparked off its silver scales as the prince dropped it on the deck of his ship, about to kill it and clean it. To his surprise, the fish stared up at him and spoke!
“O Prince, please do not kill me. If you release me, I will show you to an island no man has seen before!”
The prince, amazed that the fish could speak, felt sorry for it. He put it back in the water, even though he did not believe the fish would actually show him to land, and said, “Be free, fish!”
The fish swam around the ship, happily, and then poked its head out of the water and said, “Now, if you follow me, I will show you to the island, where my mistress lives and rules over the animals.”
The prince, still not sure if he believed the fish, decided to follow it anyway. He followed it all of that day, and just as the sun was setting, they reached land. The prince did not recognize the island, but moored his Spearfish and went ashore. Just as he set foot on the sand, a woman came walking out of the trees toward him. She was very beautiful, with golden hair and bright blue eyes.
“The fish has told me of your kindness,” she said. “Now I am hoping you may help me as well. I have lost something very important to me, my magic golden ball. It was stolen from me by a lion; he ran off into the woods. Could you go after the lion and get it back to me?”
The prince, although surprised by this turn of events, told her he would. After all, she was a beautiful lady, and he was a young man. He started off in the direction she indicated.
A few miles into the trees, the prince found signs of the lion. He followed them, eager but cautious. He tracked the lion to its cave, and saw places where its hair had rubbed off, but of the lion he could see nothing. The prince walked carefully up to the cave and peered in. He saw a glint of gold somewhere inside so he entered. There at the back of the cave was the golden ball! The prince hurried over to it and picked it up; it was cool in his hand.
At that very moment he heard a growl, and turned around. There was the lion, blocking the entrance of the cave! The prince drew his sword with his right hand, holding the ball in his left.
“Give it back to me,” the lion growled, threatening the prince with a massive paw. “It belongs to me.”
The prince shook his head. “It belongs to a lady. She has asked me to give it back to her. I will not fail.”
The lion roared furiously and leaped at the prince, who dodged aside. The two battled in the cave, one using teeth and claws, the other using his sword, until at last the prince saw an opening. He ducked under a swipe of the lion’s paw, moved in, and was about to run his sword through the lion’s chest when the lion looked down at him, and the prince locked eyes with it. He dropped his sword with a clatter, and instead held the golden ball out to the lion.
“Here is your treasure, lady,” the prince said.
The lion roared, and then transformed back into the beautiful woman.
“You have done well,” she said. “You are both kind and clever. You are worthy of being king after your father.”
After that, the magical lady from the island went home with the prince in the Spearfish, and when they arrived back at the castle, she became his wife, and they lived happily ever after.