Ontario assessment, in plain terms

Growing Success is 100 pages. Most of what a classroom teacher needs from it fits on a few. These are the parts that actually change how you mark.

Written by a practising Ontario teacher · Last reviewed: September 2026

Where to start

If you are new to Ontario assessment, or new to teaching here from another jurisdiction, the four ideas below carry most of the weight. Everything else is detail built on them.

The achievement chart (KATC)

Knowledge, Thinking, Communication, Application — what each category means and how to weight it.

Levels and percentages

How Level 4/3/2/1 maps to a percentage, and where the mapping stops being arithmetic. Coming soon.

Learning skills

The six skills, E/G/S/N, and why they are reported separately from achievement. Coming soon.

Growing Success in practice

Most recent and most consistent, professional judgement, and what the policy actually requires. Coming soon.

The one principle underneath all of it

Ontario assessment rests on a claim that sounds obvious and changes everything once you take it seriously: a report card mark should describe what a student can do now, not the average of everything they have ever done.

That is why Growing Success asks for most recent and most consistent evidence rather than a straight mean, why achievement and learning skills are reported separately, and why professional judgement is named in the policy rather than designed out of it.

A gradebook that only ever computes a mean is quietly arguing with the policy. That is a defensible choice, but it should be a choice.

Read the policy itself

These pages are one teacher’s reading, not a substitute for the document. Growing Success is published by the Ministry of Education and is the authority. Where this guide and the policy disagree, the policy is right and I would like to know about it.

Frequently asked questions

Is KATC a Ministry term?

No. The Ministry calls it the achievement chart, with four categories: Knowledge and Understanding, Thinking, Communication, and Application. "KATC" is staffroom shorthand for those four, and you will see the letters ordered differently by different people.

Do the four categories have to be weighted equally?

The Ministry does not mandate equal weighting. The achievement chart says the four categories are to be considered as interrelated and all must be assessed, and curriculum documents indicate emphasis by subject. Equal weighting is a common default, not a rule.

Can I just average everything?

You can, and many gradebooks do it by default. Growing Success asks for the most recent and most consistent evidence of achievement, which a straight mean does not give you — an early failed test weighs the same as a later demonstration of the same skill.

Do learning skills affect the mark?

No. Learning skills and work habits are reported separately from achievement, on their own E/G/S/N scale. A late penalty that lowers an achievement mark is mixing the two, which the policy explicitly cautions against.

Report card comments from your gradebook — written from real marks, not a blank box
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