Unlike the First Children's League, the second would be formed under the oversight of a much larger organization, the Global Justice Network, otherwise known as the GJN, an international spy agency akin to SHIELD or WOOHP. Brainstormed by Dr. Betty Director, then Chief Director of the GJN, the Second Children's League was created in response to the rise of several terrestrial, and even extraterrestrial, threats to peace on Earth in the early 2000's. While several other organizations like the Skyway Patrol, Plumbers, Men in Black, and the mysterious Crystal Gems did their best to quell these threats it became clear that more resources were needed. Thus, Dr. Director came up with the idea of creating a League of young heroes who would not only be used to help in the international effort to stop metahuman crime but also be properly trained and supervised to ensure they would become the new generation of heroes that the new millennium needed.

While many in the GJN were hesitant to recruit children and teenagers, Dr. Director was able to put their fears to rest by revealing that Kimberly Ann Possible had already been scouted into leading the new League, with highly decorated GJN agent Will Du acting as its handler. The Teen Team was formed in the last months of 2005. This young League of heroes had as its members;

Kimberly Ann Possible: One of GJN's most prominent and dependable freelance agents, Kimberly, or Kim, was already world renowned before her association with GJN or the Teen Team, being a crimefighting prodigy in the same vein as historical predecessors Tom Swyft, Nancy Drew, and Dick Grayson. Gifted with almost preternatural gymnastic skills and an optimistic drive to succeed, Kim was chosen to lead this new League on account her experience with combating various supervillains, but also because of her loyalty to GJN. As a leader, Kim was said to have been exemplary, managing to gain the respect and trust of all of her teammates easily by virtue of her charisma and competence.

Jimmy Neutron: Another boy genius with an extraordinary talent for inventions, this native of Retroville, USA was in many ways a contemporary to the Science Club's Dexter, both having a genius intellect, improbable laboratories of their own making, and a knack for creating destructive inventions by accident. That said, those who had the opportunity to get to know both boy-geniuses have said that Jimmy was the much more agreeable and sociable of the two. For that reason, he was chosen over a still active Dexter (or DexStar as he preferred to be called during this time) to join the Teen Team as both Dr. Director and Agent Du worried that Dexter's anti-social habits and mild megalomania could endanger the League. Jimmy served a the vital role in group, essentially acting as its 2x4 Technology Officer in-charge of studying and explaining the various scientific and technological oddities that the League would encounter on a regular basis. While originally disappointed that he wouldn't be leading the League despite his intellect and experience leading Team Neutron, Jimmy is said to have quickly bounced back and put this total effort in serving the team.

Juniper Lee: Directly descended from generations of Chinese magicians and shamans, Jupiter was the current Te Xuan Ze, a magical guardian of the west coast city of Orchid Bay, meant to protect the city from the supernatural activity that plagued it. As the Te Xuan Ze, Jupiter inherited superhuman physical abilities along with the power to perform magical spells and rituals. These magical talents were one of the primary reasons why she was selected for the League. Jupiter was said to have resented the demanding nature of her Te Xuan Ze duties and saw her recruitment as a convenient excuse to leave her hometown and see more of the world. Regardless of the truth of this rumor, several witness accounts paint Jupiter as being committed to the Teen Team and being enthusiastic about her involvement with it throughout her membership and even after its dissolution.

Daniel Fenton: Given spectral abilities after a mishap in his parent's laboratory, Daniel, or Danny, took on the moniker of Danny Phantom and became the local superhero of the small town of Amity Park. Danny was a relatively normal teenage boy (his half-ghost nature being the obvious exception) and was noted as being sometimes awkward around his teammates when not on missions. If this is true than it comes in sharp contrast to his behavior when on a mission for the Teen Team, as he was reported to have been something of a wise-cracking trickster when battling enemies. While he was not as well-rounded as the rest of the team due to almost entirely fighting ghosts, Danny still gave it his all and approached the weird new enemies he faced with confidence.

Jennifer Wakeman: An android created by famous Sky Patrol roboticist and engineer, Nora Wakeman, Jennifer, otherwise known as XJ9 or Jenny, was made to defend the Earth from the Cluster, a race of xenophobic machines hell-bent of destroying all organic life. Jenny was one of the first recruited into the Teen Team, her mother having headed several collaboration projects between the Sky Patrol and GJN. Despite technically being non-human, Jenny was a fully self-aware being whose mind and personality was strikingly human, with her very much acting like a typical teenage with doubts, fears, and insecurities but also a passion for adventure and a desire to excel. As a part of the Teen Team, Jenny was arguably its strongest member, her body possessing an array of advanced weaponry. Socially, she bonded with her teammates rather quickly, with none of them being prejudiced against her robotic nature.

Benjamin Tennyson: The youngest member of the Teen Team at only ten-years-old, Ben was wielder of the Omnitrix, a device of alien origins that allowed its user to transform into various aliens and possess their unique physiological abilities. The grandson of legendary Plumber agent Maxwell Tennyson, Ben had spent the summer of 2005 fighting several alien threats with his grandpa and cousin after accidentally bonding with the Omnitrix. When the summer had ended Ben became a junior member of the Plumbers working alongside his grandfather to deal with hostile aliens and learn how to better control the Omnitrix. When senior members of the Plumbers asked Ben if he would be their representative on the Teen Team, he jumped at the chance. While sometimes childish, brash and altogether inexperienced, Ben eventually did mature and become responsible as he adventured alongside the other members of the Teen Team.

Once recruited and brought together at GJN's international headquarters in New York City, Agent Du put the newly assembled Teen Team through a crash course in teamwork tactics along with individual training regimens. Once he believed the group was finally mission ready, they were officially announced to the public with a conference showcasing the "World's Newest Heroes."

The Teen Team would only exist for five years between 2005 and 2010. In that time group acted as junior superheroes, going on various missions for the GJN, essentially functioning like previous generation's government sponsored superteams like the Avengers and Justice League. Notably, this comes in sharp contrast to the First and Third Children Leagues, which were both private associations with no government of any oversight.

While most of the missions the Teen Team undertook were publicized, with some of their adventures even being retold in animated cartoons for young audiences, a few were kept secret for fear of the public's reaction to the dangers that the teenagers (and in Ben's case, preteen) had to face. The Dr. Director was especially keen on his point as she feared revealing the dangers would discourage other potential heroes from taking up the mantle of the Teen Team once they were evitability decommissioned. With that said, here are only some of the missions that the Teen Team undertook in their five-year tenure;

- In the small city of Dimmsdale, California they put a stop to a young boy's reality-warping wishes by banishing his magical "godparents" back to their realm by having Danny possess him and then wish them away forever. Afterward, the team made sure to put the boy in Child Protective Services after discovering his real parents were dangerously negligent, which was the reason he was given godparents in the first place.

- One of their earliest missions had the Teen Team team-up with a shapeshifting "American Dragon" and prevent the anti-magic Huntsclan from exterminating a benign community of monsters living under New York City's Fresh Kills Landfill. With the American Dragon's knowledge of the city and the Huntsclan, the Teen Team was able to reach the monster commune before the Huntsclan could. They used that time to create a portal using Jupiter's magic to excavate the creatures quickly. When the Huntsclan finally arrived the Teen Team was more than ready for them.

- Joining forces with the Teen Titans, the two teams successfully foiled the evil time traveler and rogue Time Agent, Warp scheme to assassinate the ancestor of superhero chrononaut Rip Hunter, one of his enemies from the far future. The technological know-how of Jimmy and Victor Stone was especially useful in this mission as Warp used reprogrammed robots from an alternate future as his assassins. Unfortunately, while they did manage to stop Warp from erasing Rip Hunter from history, they failed to capture the man himself and he would swear vengeance against the Teen Team for their interference in his plans.

- Like many of the Leagues that came before it, the Teen Team went on several exploratory missions, many of which at the urging of Jimmy. They explored the two-dimensional realm of the Chalkzone, took an undersea voyage to the Bikini Atoll where they discovered an entire underwater city inhabited by intelligent sea animals, and using Te Xuan Ze portal magic, they went to a wondrous parallel universe where martial elementalists and spirits were commonplace. However, besides those voyages and several others, their longest adventure was a six months voyage into space. Using a rocketship of Jimmy's design, they were meant to only reestablish contact with lost Plumber cells and stations scattered across the galaxy, but along the way, they found time to liberate several planets from the tyranny of various alien empires, a move that would have serious consequences for the Teen Team's future.

- Stopping a cabal of rogue agents from the Plumbers, Skyway Patrol and Men in Black who had come to believe that the UN's current policy of welcoming friendly aliens to Earth would eventually spell humanity's doom. The Teen Team caught wind of this conspiracy after a seemingly deranged teenage boy broke into their headquarters (nearly getting himself killed in the process) and demanded they see his evidence of the conspiracy's existence. As it turned out, the conspiracy had planned a false flag operation called Project: Clean Sweep, which if successful would have led to the deaths of thousands via a fleet of reprogrammed alien drones. The cabal planned on pinning the attack on alien extremists on Earth to stir enough anti-alien sentiment that the UN would be forced to abandon its xenophile policies. Fortunately, the Teen Team was able to find the conspiracy's base of operations, an abandoned Plumber base in New Mexico, and prevent the plot from occurring. This mission, of course, was classified, and despite protests from the Teen Team, the conspiracy theorist who told them about it in the first place had his memories erased to maintain secrecy.

- To the new KND recruits reading this who don't already know, the Kids Next Door had been considered a terrorist group by the adult-dominated governments of the world since its seventh reformation. As a result, we've suffered no end of attacks from agents sent by ageist tyrants. Unfortunately, the Teen Team was one of those groups, being ordered by the GJN to arrest the legendary operatives of Sector V after they had assaulted the villain Mr. Boss, a major sponsor of the GJN. The Teen Team initiated their attack against Sector V's Treehouse by having Danny and Kim infiltrate it, and with Jimmy's hacking skills, lower its defense grid, allowing the rest of the team to launch an all-out attack. Despite the superteam having an array of metahuman abilities Sector V managed to hold their own using their 2x4 tech. In the end, their battle came to a truce when Numbuh 5 (future Supreme Leader of the KND) was able to convince both sides to temporarily stop fighting. Once she was able to explain that Sector V had attacked Mr. Boss because the villain had tried to destroy our Super Convention Center in New York City so he could build a luxury hotel on its remains and didn't care that several hundred operatives would have died in the process, Kim ordered the Teen Team to stand down. Later they would bring evidence of Mr. Boss' crime to Dr. Director who promptly ordered him arrested. This incident would be a step toward the KND finally losing its international pariah status in the 2010s.

- When the villain Warp finally had enough resources to seek his vengeance against the Teen Team, he forcibly split the team into pairs and banished them into three different alternate futures. Each one was a nightmarish dystopia where youths were oppressed in some horrific way. Kim and Jimmy found themselves trapped in a massive maze and had to use both their talents (Kim's acrobatics and Jimmy's eidetic memory) to not only escape it alive but also protect the amnesiac children trapped there as well. Danny and Jenny on the other hand were sent to a future where teenagers were forcibly categorized into different factions and occupations based on the results of a complex test. Jupiter and Ben were put in the worst of these possible futures, there's being an alternate America run by an insane dictator that every year forced the children of the underclass to fight in death matches for the amusement of urban elites. When Jupiter and Ben were captured trying to stop this world's violent "peacekeepers" they were themselves put into one of these tournaments and forced to fight for their lives. It was only with the help of a family of Time Squad agents and their spiritual predecessor and successor teams that the Teen Team was able to escape these futures and make their way to Warp's base of operations in the 51st century and finally end an end to the villain.

- Battling the numerous villains of the era, the Teen Team were responsible for arresting several supervillains and terrorist groups. For instance, they saved the platypus from extinction from the Dr. Doofenshmirtz mad plan to wipe them out, they finally shutdown the lab of the Test twins who were running illegal experiments on their own brother, they once again teamed up with the Teen Titans to ensure the Brotherhood of Evil would never menace young heroes again, and they even went on a joint operation with Sector V to prevent the Delightful Children From Down the Lane from unleashing a phage that would have permanently turned the KND's vault of candy supplies into broccoli. Along with these more notable exploits they also fought against the traitorous Teen Ninjas (which cemented their positive relations with the KND), the ingenious Professor Dementor, the boy billionaire Eustace Strych, a rebuilt Armagedroid, the ineffective Box Ghost, Zombozo and his circus of fear, the H.A.M organization, and their own villainous counterparts from the Dark Matter Dimension.

- Referred to as the "Second Big Teamup" in the Book of KND, this cosmic event was a consequence of the Teen Team's aforementioned liberation campaigns during their six-month stint in space. Fearing that these actions were a preamble to Earth getting involved in another Intergalactic War, the Cluster Singularity, Yokian Theocracy, and Irken Empire banded together under the leadership of Vilgax the Conqueror to eradicate humanity before this possibility could occur. Warned of the alliance's approach by Plumber agents, the Teen Team gathered what allies they could at short notice. While several organizations did come to the Teen Team's distress, like the Plumbers, GJN, Skyway Patrol, Men in Black, The Center, Teen Titans, and of course, the KND, it was all seemingly for naught as when the alien alliance's fleet reached Earth it didn't immediately attack. Instead, they hijacked the Earth's telecommunication network and Vilgax himself sent a message demanding the surrender of the Teen Team in exchange for the Earth being spared. While more than a little cynical about Vilgax actually keeping his word, Ben most all of, the Teen Team knew that a battle against the fleet could mean the death of millions, with Jimmy calculating even worse figures. Thus, Kim put it to a vote whether they would give themselves up or fight with the rest of their allies. The vote was unanimous. Sneaking out their base, and knocking out Agent Du when he tried to stop them, the Teen Team took Jimmy's rocket and gave themselves up to the invaders. Put on trial in the fleet mothership for their "crimes" against the assembled alien dictators, the Teen Team was swiftly sentenced to death, with Vilgax being granted the honor of carrying out the sentence. Fortunately, the team was saved by the arrival of the Teen Titans and several KND operatives, who using Raven's shadow magic, managed to cloak their T-Ship and our KND S.P.A.C.E.R.C.H.A.S.E.R.'s from the fleet's sensors. With the assembled alien warlords caught by surprise a battle broke out in the mothership, Ben taking on Vilgax while everyone else battled Cluster robots, Yokian paladins, and Irken elites. In the end, Ben managed to seemingly destroy his archenemy, allowing everyone to make their escape from the mothership, which Vilgax had set to self-destruct once it became clear he was outmatched. With Vilgax and most of their leadership gone, the fleet quickly fell apart with many fleeing back to their homeworlds while others became to attack one another, believing that they had been betrayed by their allies. This gave the Terran fleet the opportunity to destroy the remaining uncoordinated alien ships, winning the battle.

While the Teen Team didn't end immediately after the Second Big Teamup, its days were numbered as the teens had (with the obvious exception of XJ9 and Ben) grown into the latter stages of young adulthood. Believing that the Teen Team had served its purpose and then some, Dr. Director and Agent Du asked if they ready to be disbanded and once again act as sole heroes. The hero's sad admission in the affirmative officially spelled the end of the League.

Kim would remain an agent of the GJN while also doing her own missions as the leader of Team Possible. She's currently a senior agent of the GJN with rumors stating that she's in the running to take the current Director's place once he retires. Jimmy went back to Retroville and continued his adventures with his friends in Team Neutron before eventually going off to college. He attended Hudson University in New York City, managing graduate within the span of a year. Jimmy now teaches astronautics at Hudson, being its youngest professor ever. Jupiter likewise returned to her hometown of Orchid Bay and went right back to performing her Te Xuan Ze duties. While far more comfortable in her role, having had the opportunity to see more of the world than most people do in a lifetime, Jupiter still had a wanderlust, especially for space travel, and would eventually join the Plumbers, deputizing her younger brother to defend Orchid Bay in her absence. After going to university Danny took up the family as it were and began exploring the Ghost Zone while still acting as Amity Park's local superhero. It's said that he very recently occurred Mystery League Lydia Deetz doing a recent expedition. Similarly to Jupiter, Jenny eventually officially joined the Skyway Patrol. Her service in the outfit is said to be exemplary, with her being largely responsible for the final defeat of the Cluster and overthrow of Queen Vexus. She's currently deployed in a campaign against the Diamond Authority in the Sagittarius Arm, a conflict that unfortunately seems likely to explode into another Intergalactic War if it continues to escalate. Lastly, Ben's future has been difficult to accurately recount. While there is evidence that Ben as a teenager would continue to fight alien threats to the Earth with his cousin, there are other, weirder accounts that say he somehow regressed in age and went on adventures nearly identically to the ones he had before he joined the Teen Team. Attempts have been made to get in contact with the time traveler Doctor Paradox, the man most likely to understand this contradiction, but so far we can only guess at what is causing these divergent timelines.

The Second Children's League was far and away the most successfully, completing more missions that both its short-lived predecessor and it's until ongoing successor. While one could chalk this up to the Teen Team simply having more resources due to its connection to the GJN, it can't be ignored that the League had a roster of diverse talents and expertise that made it so effective. Furthermore, despite Ben's early immaturity, the team was highly cooperative, possessing a teamwork dynamic that any KND Sector could, and should, learn from.