"Wizard Girl Ambitious" centers on a young girl named Rina, who dreams of becoming a powerful wizard in a world where magic is a highly regulated and competitive field. The story begins with Rina enrolling in a prestigious magic academy, where students are trained to harness their magical abilities and compete for the title of "Grand Wizard." The academy is structured around a rigorous ranking system, and students must complete challenging tasks and exams to advance. Rina, despite her lack of natural talent, is determined to rise through the ranks through sheer effort and ingenuity.

The narrative explores Rina's relationships with her classmates, including her rival, a prodigious wizard named Lina, who excels effortlessly in magic. Lina initially dismisses Rina as unworthy of competition, but their dynamic evolves as Rina's persistence begins to yield results. Another key character is Hiro, a supportive friend who helps Rina navigate the academy's challenges, often providing emotional and tactical support. The series also introduces a mysterious mentor figure, Professor Elric, who recognizes Rina's potential and guides her in unconventional ways.

As the story progresses, Rina faces increasingly difficult trials, both academic and personal. These include mastering complex spells, overcoming self-doubt, and dealing with the politics of the academy, where favoritism and sabotage are not uncommon. The plot delves into themes of perseverance, friendship, and the ethical use of magic, as Rina uncovers a hidden conspiracy within the academy that threatens the balance of the magical world. The series balances lighthearted moments of school life with intense magical battles and dramatic revelations, culminating in a climactic showdown where Rina must prove her worth and confront the forces undermining the academy's integrity.