STOCKTON - When Ajaypal Singh was 4, she memorized her first prayer. Eight years later, at the historic Sikh temple in south Stockton on Saturday, the Fremont girl recited 18 prayers from memory; it took half an hour. "It's really hard," she said afterward, smiling while playing in a crowded courtyard with about 130 other children from across the Central Valley and the Bay Area. Singh may never learn all 1,430 pages of the Guru Granth Sahib - the Sikh holy book - but she'll study and remember everything she can, as will thousands of others. It is central to their faith and tradition. "They're words from God. We try to understand what God wants us to do - the right thing to do," said Jashanpreet Singh, 14, of Stockton. This is the fourth year that the Sikh community has tested the children's scriptural knowledge in a friendly and fun way, offering prizes for those who are best at reciting the holy prayers in Punjabi. The children, wearing traditional Sikh attire including turbans, robes, bracelets and sheathed swords, sat cross-legged in the soft-carpeted main hall of the temple; they spoke softly while judges consulted the holy books and checked for accuracy. Even 5-year-old Inderveer Singh of Manteca did his best to recall the gurbanis, or words of the gurus. "Some 5-year-olds, they know a lot," said judge Iqbal Kaur. The boy's mother said she was proud; Inderveer's parents work with him every night. The words that are recited contain many Sikh principles: Work honestly, donate earnings to the poor and remember God always, said Joginder Singh, secretary at the temple. Sikhs believe in one God and maintain that all human beings are equal. "Don't do anything bad for anyone," Joginder Singh said. "No hate, no discrimination." Inside the main hall, the children were quiet; outside, during a lunch break, they threw a ball against the wall and jostled for the rebound. They're still children, after all. The parents didn't mind; the children did well that day. "When they start from the beginning, it's easy," said Jarnail Singh Lallria, whose family traveled from Livingston. "They should learn to stay close to their religion and close to their culture."