Math Kangaroo Preparation Course: Kangourou sans Frontieres Training

The largest maths competition in the world

Kangourou sans Frontieres runs in a large number of countries and is taken by an enormous number of students each year, with papers set at several levels by age group. Its scale is not the interesting part, though. The interesting part is the deliberate design of the problems.

Kangaroo questions are approachable on the surface. They are often illustrated, set in a concrete situation, and written so that a student starts thinking about them before noticing how much reasoning they require. That is a design decision, and it is why the competition works as a first contest for students who would find a bare page of abstract problems off-putting.

Seeing rather than calculating

A signature of the contest is the visual and spatial problem. Nets folded into solids, paths through a grid, symmetry, shapes dissected and rearranged.

These reward a particular habit: drawing the figure properly, drawing it large enough to work with, and drawing a second one when the first turns out to mislead. Students who try to hold these problems in their head lose them; students who commit to paper usually find the answer becomes visible.

This is trainable, and six weeks of the course are given to it. It also happens to be the part students enjoy most, which matters in a first competition.

Logic worked in writing

Constraint and deduction puzzles appear throughout. Several statements narrow a situation, and the answer follows from what cannot be true.

The common approach is guess-and-check, which succeeds on the easy ones and stalls on the rest. We teach systematic elimination recorded on paper: tracking what each statement rules out until one possibility survives. Students find this slower for a fortnight and then considerably faster.

Scoring changes strategy

Kangaroo papers have historically weighted questions by difficulty and, in many countries, applied a penalty for wrong answers alongside a starting score. That combination changes the arithmetic of guessing in a way students rarely think through.

If a wrong answer costs something and a blank does not, then a wild guess on a hard question is a bad trade while an educated guess between two remaining options is usually a good one. Where the rules differ, the strategy differs. Because the specifics are set by national organisers and have varied, we teach this against the current official rules rather than a remembered scheme, and we teach students to read the instructions on the day instead of assuming.

Sitting the right level

The contest runs at several levels by age, and preparation is worth little if it is pitched to the wrong one. We confirm the student level against the current national specification before beginning.

How the classes run

Sessions are live and online, one-on-one or in small groups of two to six. Students work problems during the session while the teacher watches the approach, since on visual problems the difference between success and failure is usually a decision made in the first thirty seconds.

The closing weeks are timed past papers at the student level, reviewed for pace as much as for accuracy, because running out of time is the most common way a capable student underperforms here.

Who this suits

Students comfortable with arithmetic for their year who enjoy puzzles. It is one of the best possible first competitions, and it remains worth sitting for strong students because the later questions are genuinely hard.

Levels, dates, scoring rules and registration are set by the national organiser in each country and vary. Check your country official Kangaroo site for the current cycle rather than relying on details reproduced on a coaching page.