Kids&Us · 2023–2024 · p. 2–7 Evaluation before launch

Learning Meter

Speaking and writing activities inside MyWay, Kids&Us’s gamified app for children aged 8 to 12 learning English as a second language. A child speaks into a game and ten words come back telling them what to fix, marked by AI against a teacher’s rubric. Getting those ten words right meant building the thing underneath: rubrics, anchor answers, a test set, and an evaluation loop that ran before anything reached a child.

In the press Kids&Us mejora la participación de su alumnado en un 40% con la IA de Microsoft Microsoft Source EMEA, 16 January 2025 · Microsoft’s write-up of MyWay and the Azure OpenAI services behind it

Where it sits

The activities the Learning Meter sits inside

MyWay teaches through short activities, each one framed as a game and marked in the corner with how it will be answered. The Learning Meter reads the speaking and writing ones, where a child produces the language themselves.

A MyWay activity intro screen titled Recipe Rush on a patterned teal background. A card reads: first,
            complete the recipe, then follow the steps by using the correct utensils and carrying out the correct
            actions. A Play button sits below it, and a drag-and-drop icon marks the activity type in the corner.
An activity opensThe task in a child’s own words, and the activity type marked before they start.
The Recipe Rush activity. A torn recipe card taped to a mint green patterned background reads: chop the
            onion and fry it in some olive oil. A knife, a frying pan, a pot boiling on a hob, a wooden spoon and an
            oven are laid out below it.
The task itselfThe instruction stays on screen while a child picks the utensils and carries out the actions in order.
A MyWay listening activity. Three restaurant fronts sit across a patterned teal background: a sushi
            restaurant, an Italian one and a burger bar. A character avatar with a speaker bubble sits below them, and
            a multiple-choice icon marks the activity type in the corner.
A different typeAudio plays from the character, and a child answers by choosing. The corner icon carries the change.

Product screens from MyWay. The artwork, characters and activity content are Kids&Us’s.

Step 1The rubric I wrote

Four bands, each with anchor answers for every activity

The model never scored against “good English” in general. For every mini-activity it got the question, what to check, and a real example answer at each band. It could choose any score from 20 to 100, anchored to these four.

Step 2The rubric, running

Follow one answer through the Learning Meter

This work lived in Jupyter notebooks, rubric spreadsheets and model runs, and what a child saw at the end of it was ten words of feedback. The walkthrough rebuilds the pipeline so the stages in between are visible: the same rubric, the same anchor answers, the same scores. Switch between the first prompts and the tuned ones to see what the evaluation loop changed.

Speaking · image prompt · AP1
What time is it?

Pick what the child said
Step 3The test set

About 4,000 answers with known scores, before anything reached a child

Real answers came from children in the pilot schools, cleaned and scored by hand. Synthetic answers I wrote to stress-test it, covering the edge cases real data was thin on: other languages, fragments, and the near-misses a lenient model waves through.

Double-scoring, to catch drift

Every answer in the set was graded twice, so the same answer scoring differently on two runs showed up as a number rather than as a complaint after launch. Model settings were kept low-creativity for the same reason: grading has to be repeatable before it can be trusted.

Step 4Before and after

Did it get more trustworthy?

100%of responses came back as a valid score plus feedback
≈1–2 stypical response, with rare peaks near 10 s
Design decisions

What I decided, and why

Feedback in ten words or fewer, spoken to a child

Feedback is read mid-game, so it is short, in the first person, names the fix, and stays strict on the score.

Anything not in English scores 0

A correct idea in another language is still a miss in a language course, so it became a hard rule in every prompt.

Reuse scores for answers already seen

Children give many of the same answers. Matching them first made scoring instant and cheaper, and it made the same answer always get the same score.

What this showsDesigning AI experiencesEvaluation before launch

Where I worked across the lifecycle

From writing the rubric to the accuracy numbers that decided what shipped, and the handoff that kept it running.

This demo is scripted, on purpose. The real Learning Meter ran on Kids&Us systems, on children’s voice and writing data. I have since left the organisation, so the live model isn’t mine to run. Every answer here is pre-scored from my own rubric, prompt databases and test results. No child data is shown, and all figures are rounded.