MYP Maths Investigating Patterns Tasks: Criterion B Explained

You answer them by moving through four stages: generate simple cases, spot a numerical or visual pattern, describe it in words then in a general algebraic rule, and finally justify or prove why the rule works. Criterion B rewards the reasoning trail, not just the final formula.

Criterion B — Investigating Patterns — assesses a student's ability to select mathematical problem-solving techniques, describe patterns as relationships/rules, and generalise correctly. According to the MYP: Mathematics guide, it's marked out of 8, alongside Criteria A, C and D, each also out of 8.

A level 7-8 response selects an efficient strategy, states a correct general rule with full justification of why it works, and tests the rule against an unfamiliar case with a clear explanation of the result. It reads like a mini mathematical argument, not a list of numbers.

Start with the differences between consecutive terms. A constant first difference means a linear rule (an + b); a constant second difference means quadratic (an² + bn + c). Use two or three known terms to solve for the constants, then verify against a term you haven't used yet.

The most common mistake is jumping straight to a formula without showing the reasoning — markers can't award justification marks for work they can't see. Other frequent losses: not testing the rule on an unseen case, and describing the pattern only in words with no algebraic generalisation at all.

Spend roughly a third of your total time exploring cases and testing ideas on rough paper before you write the formal response. Rushing straight into a write-up usually means backtracking later when a rule turns out wrong, which costs more time than planning would have.

No — they're different criteria. Criterion B focuses on spotting and generalising abstract or numerical patterns, while Criterion D asks students to apply mathematics to a genuine real-world context and evaluate the reasonableness of their model. A single task can sometimes touch both, but they're marked separately.

There's no fixed IB-mandated number — each school's maths department designs its own Criterion B tasks across the year, typically two to four per year in MYP 4-5, alongside tasks covering the other three criteria. Ask your child's teacher for the school's specific assessment calendar.

MYP Criterion B tasks are shorter, teacher-set investigations focused specifically on generalising a pattern. The DP Mathematics AA/AI internal assessment (the exploration) is a longer, student-chosen investigation worth 20% of the final grade and doesn't have to involve patterns at all — it's a much broader piece of independent work.

Practising with genuine number and shape sequences — not just textbook drills — builds the pattern-recognition instinct examiners reward. On RevisionPrep, Topical Worksheets for MYP Mathematics include sequence-generalisation practice with mark-scheme-style feedback so you can see exactly where a response would gain or lose Criterion B marks.

Yes — self-study resources like Revision Notes and Topical Worksheets let students practise generalising patterns independently between school-set tasks, which is usually more useful than generic textbook repetition since it targets the exact skill Criterion B assesses: describing and justifying a rule.