This involved some reduction in the family's standard of living, but it did not affect the children's lives. Later on, Fritz Boye became an inspector in the Swedish Private Insurance Supervisory Service. At her new school, Karin made friends with a few girls of similarly introspective and imaginative temperament. Together they read the works of Dumas, Rydyard Kipling, H.G. Wells and Maeterlinck, and also those of Rabindranath Tagore. Tagore's poetry seems to have made an especially strong impression on the young Karin Boye : she immersed herself in Indian mythology, and sought to experience the country itself through Karl Gjellerup's Indian novel Pilgrimen Kamanita ('Kamanita the Pilgrim'). Above all, she studied Buddhism, and made serious efforts to learn Sanskrit. With her friend Signe Myrbäck as 'disciple', Karin played the role of guru, and the two girls would sit crosslegged on the lawn together, practising the art of breathing in and out. Signe Myrbäck relates that when their ecclesiastical history teacher once told the class that Sweden had only a small minority of Buddhists, Karin claimed to be one of them. Her history teacher, Lydia Wahlström , also once made some slightly disparaging remarks about Buddhists during a lesson, and Karin Boye put up her hand and said sternly: 'I'm a Buddhist!'

During her last two years at school, Karin Boye moved away from Buddhism and towards Christianity. Many of her schoolfriends found it hard to understand how she could have accepted Christianity, as previously she had always talked about it with cynicism and a kind of dry laughter. At first, the change seems to have been a source of happiness and self-discovery for her. Buddhism had become a life-denying influence on her, and for the first time she began to experience a sense of personal and inner freedom. At this time, she kept diaries. These are mostly of an 'inner' nature, containing meditations on religious experience. In one passage she describes how she came to her religious awakening:

Now I have reached the age of twelve or thirteen, the borderland between child and young person. Like a milestone shines the memory of one single book: Kipling's Kim . It is the last of my childhood books that I remember, and at the same time the one that probably meant most for my development.

In the moving figure of Teshu Lama, religion entered my life for the first time as a living reality. That may seem strange for a child who had had a good Christian upbringing. But the child's religion is often so far from deserving the name 'religion' that it seems to me fruitless - with perhaps only a few exceptions - to offer a child the divine beauty of the Gospels, and a sacrilege to set the Gospel stories as homework. For me 'the Bible stories' were worn, everyday, already too well-known, when the hunger for religion began to awake. Teshu Lama - prepared by Puran Bhagat of The Jungle Book - came like a message from a world that had hitherto been closed, and I trembled, and I fell down and adored.

At the age of eighteen, she experienced a liberation and a transformation: an entry from the summer of 1918 reads: 'Domine , rex , venisti , vidisti , vicisti .' And on the eve of 1919: 'My birth-year is at an end.'

The diaries also concern Karin Boye's experiences not only at school, but also at Christian summer camps, where she seems to have approached the fairly routine group discussions with extraordinary intensity, forming close attachments to other girls and women in the groups. Two such relationships seem to have been particularly important for her. Agnes Fellenius , one of her classmates with whom she mutually shared all secrets, became quite severely depressed because of conflicts within her home, and Karin Boye took it upon herself to rescue her from the effects of this. She began to supervise Agnes' schoolwork, and made her take the final school examinations, trying by strength of willpower to make her pass, which she did. Margit Abenius describes how Karin stood outside the examination room, 'wrapped in intense concentration and the desire for a good outcome'.

The other important relationship was with Anita Nathorst , a woman who was seven years older than her and was a student of theology and the humanities at Uppsala University. At the Christian summer camp Karin attended at Fogelstad , Anita Nathorst was a group 'mother', looking after the young female students. Karin Boye wrote to her friend Signe Karlsson :

Our 'mother' was Astrid Nathorst's sister, Anita Nathorst . Do you know who she is? Oh Signe, such a person! She is so wonderful! One day Ruth, Brita, Daisy and I carried blankets out into the park (it was immensely large) and took Anita with us and lay and talked. I don't think I shall ever forget it.