Looking for a challenge? Try this question from the 42nd International Math Olympiad.
Problem of the Month - Math Olympiad
Math Olympiad Contest Problems for Elementary and Middle Schools, Vol. 1 [Paperback], (math olympiad problem books, mathematical problem solving, educational, gifted, mathematics, problem solving techniques, school, talented, very good)
They're No. 1: U.S. Wins Math Olympiad For First Time In 21 Years by npr #Math_Olympiad
math olympiad worksheets on mean-mode-median, measurements for grade 5 students This workbook contains worksheets on Mean, Mode and Median, Measurements, Multiple and Factors, Multiplications and Number Lines & Coordinates for Grade 5 olympiad students. There are total 12 worksheets with 210+ questions.
APSMO Maths Problem Solving Contests: Maths Olympiads and Maths Games
100 Math Brainteasers (Grade 7, 8, 9, 10). Arithmetic, Algebra and Geometry Brain Teasers, Puzzles, Games and Problems with Solutions: Math olympiad contest problems for elementary and middle schools by Zbigniew Romanowicz http://www.amazon.com/dp/1623210291/ref=cm_sw_r_pi_dp_yYHswb066C5NF