"Maruoka-san Chi no Kyouikugakari" centers on the daily life of the Maruoka family, particularly focusing on the interactions between the family members and their unique household dynamics. The story revolves around Maruoka, a young man who becomes the caretaker and educator for his younger siblings after their parents pass away. Despite his inexperience, Maruoka takes on the responsibility of raising his siblings with dedication and care, striving to provide them with a stable and nurturing environment.

The narrative explores the challenges Maruoka faces as he balances his role as a guardian with his own personal growth. His siblings, each with distinct personalities and needs, add layers of complexity to his responsibilities. The eldest sister, Aki, is mature and responsible, often assisting Maruoka in managing the household. The middle sibling, Yuki, is more carefree and mischievous, frequently causing lighthearted trouble. The youngest, Haru, is innocent and curious, requiring constant attention and guidance.

Throughout the series, the family navigates everyday situations, from school events and household chores to emotional struggles and bonding moments. The story emphasizes themes of family, responsibility, and resilience, showcasing how the Maruoka siblings support one another through life's ups and downs. The interactions between the characters are heartfelt and often humorous, highlighting the warmth and love within the family despite their hardships.

The manga also delves into Maruoka's efforts to educate his siblings, not just academically but also in life skills and moral values. His dedication to their well-being and growth is a central focus, as he learns to adapt to their individual needs and personalities. The series portrays the challenges of parenting from a young adult's perspective, blending moments of struggle with those of joy and fulfillment.

Overall, "Maruoka-san Chi no Kyouikugakari" is a slice-of-life story that captures the essence of familial bonds and the trials of stepping into a parental role. It balances emotional depth with lighthearted moments, offering a relatable and engaging portrayal of a family working together to overcome life's obstacles.