The crossword solutions for the term PREFIX WITH 'SCHOOL' OR 'MATURE' are 'PRE' (3 letters). The prefix 'pre' is derived from Latin and is used to indicate something that comes before or in front of something else. It is commonly used in combination with other words to form new words, such as 'preschool' or 'PREMATURE'. In this case, it can be used to form the words 'preschool' and 'PREMATURE', which both have the same meaning of something that comes before or is more advanced than what is expected.