5th grade Number theory Math Quiz - This a part of algebra that could be taught in a fun and innovative way in classrooms. It is usually identifying whether a number is a prime number. That would define it as s number that contains only two factors, the number one and the number itself. The calculations are usually done by finding the greatest common factor and the least common multiple. When these methods are taught it is of high importance that the children understand it. A fifth grader's knowledge of the prim factors is essential. This test consists of one challenging question to identify if it is a prime factor. Learn about counting in Roman numerals, prime and composite numbers, spelling large numbers, factors of numbers, LCM and HCM and more.