For the grade level questions that have been reworked, the questions are according to the learning outcomes at that grade level but deeper.
To prepare a team for the competition a teacher might first focus on team building and strategy.

-How might a team focus on answering a multitude of questions?
1 team mate per question?
Solve in partners?
Pass on questions for others to try when one or more of you are unsure?
Have another teammate or teammates do a double check?


-Practice to find what works for a particular team using questions gathered.

http://learn.fi.edu/school/math2/sept.html

http://www.oecd.org/pisa/test/form/

http://www.homeschoolmath.net/online/problem_solving.php

http://www.matholympiad.info/pages/somepracticeproblems.aspx

http://nrich.maths.org/teachers


For a practice session a teacher need only gather 4 or 5 problems. Also can be used are the most challenging questions (usually the last ones) from MMS lessons.