These are my season three ideas. If you don't like it, post the chapter and you may improve it. Thank you.

Season Three
1. Hidden Secrets- Aang and the gang finds out that there is someone in Ba Sing Se that is stealing from the people. When they find out who is the one, they realize that he is a firebender. Zuko finds out a terrible past about his mother.
2. The Firebender- Aang searches for the firebender to ask him to teach him since he thinks that he is harmless. Zuko leaves Iroh in Ba Sing Se to go on a quest for his mother.
3. The Tempest Flame- Aang and the gang now leaves Ba Sing Se with a new member of their gang, Han Lee. When Aang starts firebending, he must first learn about the method "The Tempest Flame." Meanwhile, Katara sees Jet when she worries about him.
4. The Lost Ones- Aang and the gang gets lost when they are stuck in a fog near the Wong Forest. Things go worse when Azula is following them. Zuko goes into a earth kingdom town when he hears rumors about a woman described to be her.
5. Element Principles- When Aang is sent to the Eastern Air Temple, he contacts Avatar Roku about his quest. Zuko is followed by a earthbender that knows that Zuko is a firebender.
6. Songhum Lake- When the gang gets split into two groups, Aang, Han Lee, and Katara, and Sokka, Toph, Momo, and Appa, they find out about a secret lair under Songhum Lake.
7. The Triumph- Appa and Momo gets stolen by a Earthbender named "Triumph" and Aang must fight him to get them back. Azula finds Zuko when he rests in Songhum Lake. She later lets him free when she finds out that Zuko wants to search for his mother.
8. Ozai Island- Aang and the gang follows a woman that leads them to a temple that predicts the future about the solar eclipes.
9. Zuko's Fear- Zuko reaches Ozai Island where he faints and the mysterious woman helps him up. Zuko starts to realize that he is Zuko's mother.
10. Hope and Destiny- Aang and the gang goes to the south pole to recrute the waterbenders when the solar eclipes happens. When the mysterious woman reveals herself, she is said that she is his mother's friend.
11. The Seekers- Aang is throwned into a tournament in a new earthbending sport with Toph. Zuko ends his mission of searching for his mother and his new quest to search for the Avatar.
12. The Quest Pt. 1- Aang and the gang reaches back to Ba Sing Se to warn them about the solar eclipes. When Zuko returns to Iroh, he finds out that Iroh is dead.
13. The Quest Pt. 2- Aang and the gang are attacked by Azula's army outside of Ba Sing Se. Zuko is alone now that he doesn't have Iroh on his side and decides to go to Jin.
14. Spiritual Message- Avatar Roku tells Aang that he must learn to use the four elements together to defeat the fire nation rain.Meanwhile, Sokka and Han Lee searches for food, but gets stuck in a cave.
15. Return To Full Moon Bay- Aang thinks that the Kyoshi warriors will help in his plan to defeat the fire nation, but they relaize that they are hurt from fighting Azula in the past.
16. Avatar Sokon- Aang learns more about the previous waterbending avatar. Zuko sneeks into the fire nation.
17. Final Battle- The gang is to fight Azula, Ty Lee, and Mai to enter the fire nation.
18. The War Pt. 1- The earth kingdom and the water tribe join forces to fight against the fire nation in an all out battle.
19. The War Pt. 2- Zuko kidnapps Aang , where leads to trouble in the war. Meanwhile, Katara, Toph, Han Lee, and Sokka all search for Aang.
20. The War Pt. 3- Aang is to fight the fire lord to the finish. He must soon use the method of using all the elements at the same time.

Now that's what I'm talking about: a three part finale!

wow dats good. uve really put a lot of thought into it. im too lazy to think that far ahead

There is a song writtin for these kind of people. It's called "Why don't you get a job?"

yeh those ideas are really good! you should pitch it to the people who make it!

Maybe you should at least wait until s2 is over with before predicting what will happen in s3. The final events of this season could alter your theories of next season drastically...

TOKKA, TOKKA, TOKKAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Copied from thread: My Avatar Fan Fiction (which you should read)
Book 3: Fire
3x1 - The Island
The Gang begins travelling and reaches a small island where they are ambushed by a savage tribe. They fight to get out, but find a lost temple of Hateru, one of the very first Avatars, who was called to beat down good to bring balance. Aang learns of the Avatar's lineage. Zuko follows in his ship and rescues Aang's party, then departs.

3x2 - Iroh Alone
Abandoned in Ba Sing Se, Iroh learns of a plot to kill Zuko and travels to catch up with his nephew. Shameless Iroh rules episode. He finds his nephew and Zuko says "Oh, that? That was yesterday. But thank you, Uncle." He travels back, smiling.

3x3 - Aang's Rage
Hateru, the past Avatar continues to haunt Aang and irritates the Avatar until he is persuaded to destroy a Fire Nation town. Zuko intervenes and he and Sokka bring the Avatar down. Aang explains the past Avatar's dark deeds.

3x4 - Venegance
Azula, Ty-lee and Mei set out to capture Aang once again, and chase them up the island chain until finally catching Aang, Toph and Katara. Sokka has escaped by chance and the episode ends with him alone.

3x05 - Sokka Alone
Sokka chases Azula, Ty-Lee and Mei on the Fire Nation's main land. He fights Ty-Lee and counters her abilities, then wins. With her help, they take down Mei and Azula. Azula departs on her own, defeated, but not before telling Sokka that she killed Suki long ago. The gang and Mei and Ty-Lee seperate.

3x06 - Old Kuzon
The gang arrives at a town named after Aang's old friend. Aang spends time there to mourn his friend's passing and finds Zuko there in the end, paying respects to his relative. The two talk some. Zuko tells Aang, "If you are going to kill my father, I will be by your side."

3x07 - Trapped!
Aang, Toph, Katara and Sokka are shot down as they fly over a Fire Nation Villiage, where the mayor plans to turn them over to the Firelord. They are freed by a resistance who frees the town. Katara and Sokka learn that there are good Fire Nation members. Aang is taught some firebending and recieves some scrolls.

3x08 - Nightmares
Aang finds himself trapped in another world of his dreams where he is tormented by Hateru. He asks Aang to bring Sozin's Comet down on the capitol. Aang awakens in the Avatar State, but Katara calms him down. She asks Aang later if he's in love with her, but he tells her no. He pushes her away and sits staring at the fire.

3x09 - The Water Tribe Warriors
Sokka and Katara find a city under siege and land on it, finding that its a battle between thier tribe and the Fire Nation. Aang and the gang join the battle and liberate another city. Sokka is given a water tribe sword by his father.

3x10 - Jeong Jeong's Plea
The gang is forced to land by a living wall of fire. It's helmed by Jeong Jeong, who further instructs Aang. He then asks Aang if he is aware that in the end he will have to murder the Firelord. Aang sees Hateru behind Jeong Jeong, who nods in agreement.

3x11 - The Resistance
The gang stops in a town, where they are contacted by a member of the resistance. The four fight to liberate another town and meet up with Rhaine, the leader of the reistance. He tells them of the plans for the new world. Aang promises to help build a world of peace.

3x12 - Azula's Ambush
In a canyon, Azula's new team (with an earthbender and a turned Water Tribe member) attack the gang. Zuko appears again and saves the day. Aang asks if he's following them. Zuko tells them he's trained to know when they're in danger through one of Iroh's practices. He takes them to a small town to rest. Katara talks to Zuko in the night, as she feels rejected by Aang. Zuko and her kiss, but Zuko leaves again. Aang watches the entire thing, Hateru antagonizing the situation.

3x13 - Avatar Hateru
In a lost age, the Priests of Light managed to discover the secrets of light and began to throw the world out of balance. We watch Hateru murder the Priests of Light and destroy thier records. We also see Koh, in the past, who aided Hateru's plans.

3x14 - Katara and Toph
Tired of being shot down, the gang takes to walking. Aang and Sokka want to go one way, Katara and Toph want to go another. Taking Appa, Katara and Toph go thier way and liberate a Fire Nation town on thier own.

3x15 - Sokka and Aang
Sokka and Aang are stuck with Momo. They go through a comedy of errors and find themselves in big trouble. Katara and Toph come back around to rescue them from a sandtrap.

3x16 - The People We Touch
We get an update on Iroh, back in Ba Sing Se, who goes through town and keeps the peace. Also, Ty-Lee and Mei have to fight the Fire Nation they used to represent. Meng watches the Fire Nation invade her town. The Guru, who helped in Season 2 is murdered by Azula.

3x17 - The Greatest Day Ever
Aang, Katara, Toph and Sokka, sick of wandering through a hot desert find themselves in a field. They spend the day relaxing, but are attacked by Azula and her troops. Sokka is stabbed and Toph is severely injured. Appa is poisoned and may die. Just when it looks like Azula has won, Hateru gets Aang's ear and forces him into the Avatar State. Aang beats Azula and flings her into the sea. Her lackies panic and run. Katara tries to calm Aang but Hateru reminds Aang of the kiss she shared with Zuko. Aang shoves her away and rockets across the sea to the capitol.

3x18 - Aang Alone
After abandoning the gaang, Aang travels the last bit to the capitol and goes to the inn to meet Zuko, who isn't there. He's attacked by Fire Nation zealots and fights them all. He is approached by a member of the resistance who teaches him a few final lessons. He is deemed a competent Firebender.

3x19-20 - The Eclipse/Under Sozin's Comet
Aang fights a one man war in the Fire Nation Capitol. It seems like he won't get closer until finally the solar eclipse takes place and the Fire Nation soldiers step aside. He enters the palace grounds and finds Sozin's Comet anchored in place directly above the palace with Ozai underneath it, absorbing its power. Under Sozin's Comet, firebending is still possible. Aang goes to end it all. To demonstrate his power, Ozai kills Azula heartlessly. Zuko comes in to join the fight.

And I like your general plot, but really don't like your titles. They sound more like Harry Potter chapters than Avatar chapters to me.

MORE SPOILERS!!! (except not really)

Chapter 5: RoX0rz ma s0xOrz!!!!!!11shift+1
When the entire water tribe (except Katara) dies of a mysterious illness, the Gaang copes with this be speaking in 133t. But what will happen when they discover that Guru Pathik is a master toiletries-bender, but won't teach Aang unless he forgoes his mAd 133t 5p3Ak1Ng 5Ki11Z????????

Chapter 6: Hey Hey HEY!
When the kids meet with Fat Albert, it is revealed that he is the carrier of the HEY HEY HEY disease, making everyone say HEY HEY HEY and nothing but. The Gaang now loses their 133t-speaking, but now they can't stop saying "Hey, hey, HEY!" However, their problem is quickly resolved when Fat Albert dies of a mysterious illness, not to mention the fact that this is Avatar and not Fat Albert, so what the is Fat Albert doing here in the first place?!

Chapter 7: Electric Chemistry
We enter by seeing Iroh die of a mysterious illness. Toph is wondering if her "electric chemistry" with the Guru is going to interfere with Aang's toiletries-bending training, now that they aren't speaking 133t, anymore. Momo and Appa finally confess their love for Katara.

Chapter 8: Appa or Momo?
Katara continues to wonder. Appa or Momo? Momo or Appa? Mopa or Apmo? She can't decide! Fortunately, she won't have to. Appa and Momo both die due to a mysterious illness. Guru says that Aang will need to start recognizing these illnesses if he is to defeat the Fire Lord.

Chapters 9-12 coming.

Note: If you believed that these are real episodes, then you need help of a professional nature.

Heh heh heh! Death by pea!

Yes, yes. It's all quite tragic. I can't wait to see the episode.

Chapter 13: Earthquake
When a huge earthquake strikes... we just did this, didn't we? Okay, so apparently nothing new happens, except that the earthquake seems to trigger diarrhea in poor Toph's bowels. She then dies a gruesome death.

Chapter 14: Face of Katara
After the entire earthbending race (except for Meng) dies, Aang and Katara was face the difficulties of their relationship now that Katara's face is a man's. Confused and hurt, Aang runs to Meng and... umm....... yeah. Later on, Sokka asks Aang what's going on with him and Meng. Aang replies that they're just friends... with benefits.

Chapter 15: I Love You (Except Not Really)
When Meng dies due to a mysterious illness, Aang goes into the Avatar State in pain. Fortunately, Kyoshi appears and calms him down before he does any damage, but Katara finds out what happened between Aang and Meng, and things don't look good.

Chapter 16: Rump Trouble
When Sokka is inflicted with diarrhea, Aang is determined not to let him die like Toph did. The Guru and Aang both team up to battle this illness, and even Kyoshi appears as well, but to no avail. Sokka dies.

Sorry if those weren't as good, but the final set should be pretty funny... (I hope.)