The episode begins with Lisa Simpson feeling frustrated with her math skills after a poor performance on a math test. She is determined to improve and seeks help from her father, Homer, who is initially dismissive of her concerns. However, Lisa's determination leads her to take matters into her own hands, and she decides to study harder.

At school, Lisa learns about a math competition called the "Mathletes" and becomes excited about the opportunity to showcase her skills. She approaches her teacher, Mrs. Krabappel, to express her interest in joining the team. Mrs. Krabappel encourages Lisa but informs her that the team is primarily composed of boys, which makes Lisa feel even more motivated to prove herself.

Meanwhile, Bart Simpson, Lisa's brother, is also dealing with his own issues. He is struggling with his own academic performance and feels overshadowed by Lisa's newfound focus on math. This leads to a rivalry between the siblings, as Bart tries to undermine Lisa's confidence in her abilities.

As the Mathletes prepare for the competition, Lisa faces challenges from her male peers, who doubt her capabilities. She experiences moments of self-doubt but is encouraged by her friends, including Milhouse and Nelson, who rally around her. They help her practice and build her confidence, emphasizing the importance of teamwork.

The day of the Mathletes competition arrives, and Lisa is nervous but determined. The competition is intense, with various rounds of challenging math problems. Lisa's knowledge and skills are put to the test, and she performs admirably, impressing both her teammates and the audience.

However, during the final round, Lisa faces a particularly difficult question that stumps her. In a moment of panic, she hesitates, and the boys on the opposing team take advantage of her uncertainty. Bart, witnessing Lisa's struggle, feels a mix of emotions, including guilt for his earlier behavior and a desire to support his sister.

In a surprising turn of events, Bart decides to step in and help Lisa by shouting out the answer from the audience. His unexpected support boosts Lisa's confidence, and she quickly regains her composure. With Bart's encouragement, Lisa answers the question correctly, leading her team to victory.

The episode concludes with Lisa celebrating her win with her friends and family, feeling proud of her accomplishments. Bart, having learned the value of supporting his sister, shares a moment of camaraderie with Lisa, and they reconcile their rivalry. The episode ends on a positive note, highlighting the importance of teamwork and family support in overcoming challenges.

In the ending of "Girls Just Want to Have Sums," Lisa Simpson successfully competes in a math competition, overcoming her insecurities and proving her abilities. Meanwhile, Bart Simpson learns a lesson about the importance of hard work and integrity. The episode concludes with a sense of accomplishment for Lisa and a newfound respect for her talents.

As the episode approaches its conclusion, the scene shifts to the math competition where Lisa is nervously preparing backstage. The atmosphere is charged with excitement and tension as students from various schools gather, each hoping to win the coveted title. Lisa, feeling the weight of expectations, reflects on her journey and the support she has received from her family, particularly from Marge, who has encouraged her to embrace her intelligence.

The competition begins, and Lisa faces off against her rival, a confident and somewhat arrogant boy named "Derek." As the questions are posed, Lisa's determination shines through. She recalls the moments of doubt she experienced earlier in the episode, where she felt overshadowed by her peers and questioned her own abilities. However, with each correct answer, her confidence builds, and she begins to enjoy the challenge.

Meanwhile, Bart, who has been struggling with his own academic issues, watches Lisa from the audience. He is initially distracted and disinterested, but as he sees Lisa excel, he starts to feel a sense of pride in his sister. This moment of realization prompts Bart to reflect on his own choices and the importance of putting in effort, even if it's not always easy or fun.

As the competition reaches its climax, Lisa faces a particularly difficult final question. The tension in the room is palpable, and the audience holds its breath. Lisa takes a deep breath, channels her focus, and answers correctly, securing her victory. The crowd erupts in applause, and Lisa beams with joy, finally feeling validated in her abilities.

In the aftermath of the competition, Lisa is awarded a trophy, and her family rushes to congratulate her. Marge hugs her tightly, expressing how proud she is of Lisa's hard work and perseverance. Lisa, filled with a sense of accomplishment, realizes that her passion for math is something to be celebrated, not hidden.

Bart, inspired by Lisa's success, approaches her and admits that he has been slacking off in school. He expresses a desire to improve and asks Lisa for help with his studies. This moment signifies a turning point for Bart, as he acknowledges the value of education and the importance of supporting one another as siblings.

The episode concludes with a heartwarming scene of the Simpson family together, celebrating Lisa's victory. The camera pans out, showing the family united and happy, highlighting the themes of support, hard work, and the importance of believing in oneself. Lisa's triumph not only elevates her status among her peers but also strengthens the bond within the Simpson family, leaving viewers with a sense of hope and inspiration.

In the episode "Girls Just Want to Have Sums" from Season 17 of The Simpsons, there is no post-credit scene. The episode concludes without any additional content after the credits roll. The focus remains on the main storyline, which revolves around Lisa's struggles with math and her eventual triumph, rather than any extra scenes or gags following the credits.

Lisa is driven by her passion for mathematics and her desire to empower her female classmates. She feels a strong sense of responsibility to help them succeed, especially after witnessing their struggles and the societal pressures they face regarding academic performance.

Initially, Bart is dismissive of the math competition and shows little interest in academics. However, as he sees Lisa's dedication and the importance of the competition, he begins to take it more seriously, ultimately leading to a moment of pride when he supports her efforts.

Principal Skinner is enthusiastic about the math competition and sees it as an opportunity to boost the school's reputation. His pressure on the students to perform well adds to the tension, particularly for Lisa, who feels the weight of expectations as she tries to lead her peers.

The other girls initially feel insecure about their math skills and are hesitant to embrace Lisa's leadership. However, as Lisa encourages them and they begin to practice together, they gain confidence and start to believe in their own abilities, fostering a sense of camaraderie.

Lisa and the girls encounter various challenges, including their own self-doubt, distractions from their peers, and the pressure of competition. They struggle with complex math problems and the fear of not measuring up, which tests their resolve and teamwork.

In "Girls Just Want to Have Sums," there are a few elements that may be considered objectionable or upsetting for children or sensitive viewers:

1. Math Anxiety: The episode explores themes of academic pressure and anxiety, particularly around math, which could resonate negatively with children who struggle in that subject.

2. Gender Stereotypes: The storyline addresses gender roles and expectations, which may include some discussions or portrayals that could be seen as reinforcing stereotypes.

3. Competitive Behavior: There are scenes depicting intense competition among students, which might be stressful or upsetting for some viewers, especially those sensitive to themes of rivalry.

4. Emotional Struggles: Characters experience feelings of inadequacy and frustration, particularly Lisa, which may evoke empathy but could also be distressing for younger viewers.

Overall, while the episode contains humorous elements typical of "The Simpsons," these themes may require parental guidance for younger audiences.