I don’t know how it is in other countries, but Spanish high school math competitions are designed to test both logic and creativity. They’ll require you to use the material from your current year, but the way in which you have to apply that math isn’t obvious if your only competency in math is specifically passing high school tests. You don’t get a good score by being a proficient human calculator, but by applying good abstract analysis, which you should be able to apply in other areas of your life.