Charles Warrell (23 April 1889 - 26 November 1995) was an English schoolteacher, and creator of the I-Spy books, a series of spotters' guides written for British children and first published in 1949. In his role as creator and publisher of the books, Warrell was known pseudonymously as Big Chief I-Spy.Warrell was born in Farmborough, Somerset in 1889. Having trained at Culham College, Abingdon, Oxfordshire, he became the headteacher at Higher Wych School in Cheshire, then later Pleasley Hill School, Mansfield, Nottinghamshire, during the 1940s. He first devised the concept for the I-Spy books in 1948, towards the end of his teaching career. He was an advocate of active learning, and originally created the books as a method of keeping children entertained and stimulated on long car journeys, and making children more aware of the world around them. Wikipedia
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