● Unit of inquiry resource
Maths in Sharing the planet
This theme is about how people and the natural world depend on each other: rights, fairness and looking after what we share. The maths inside it is measurement and data: read a gauge, count what is used, chart what is thrown away, share a limited thing fairly.
Ameera Surekha, who built Explorisle at home for one child · 26 September 2026
The theme, in one paragraph
Sharing the planet is one of the six transdisciplinary themes that IB PYP schools use to frame their units. On the island it is the first theme island past the maths world. It carries two units; a teacher sets one as the class goal and every child who joins gets it.
Unit one: Water
Central idea (the island's own words): Water is limited, and people share it.
Lines of inquiry: where water comes from; how people use water; how water is shared fairly. Concepts: causation, responsibility, connection.
| Station | What the child does | The maths |
|---|---|---|
| Rain gauge | reads the gauge and the jug | Measurement: capacity, reading a scale |
| The buckets | counts and groups what a day uses | Number: counting, grouping, the tables |
| Share the tank | splits a tank between homes | Number: division as fair sharing |
The decision post, The dry week: The tank is low. Give the farm more, share it equally, or save it for later? There is no wrong answer; the child gives a reason, and the reason lands on the class sheet.
The exhibit: finish the stations and the child earns a well for their own plot.
Unit two: Waste
Central idea (the island's own words): What we throw away goes somewhere, and we choose where.
Lines of inquiry: what we throw away; where it goes; what we can change. Concepts: responsibility, change, connection.
| Station | What the child does | The maths |
|---|---|---|
| The bin survey | reads the chart of what the class threw away | Data handling: pictograms and bar charts |
| Round again | puts a bottle's life in order | Sequence and cycle |
| The weigh-in | measures a week of waste | Measurement: mass |
The decision post, One thing: If the class changes one thing, which: plastic bottles, paper, food waste? There is no wrong answer; the child gives a reason, and the reason lands on the class sheet.
The exhibit: finish the stations and the child earns a well for their own plot.
Tasks for the classroom without a screen
- A litre jug, a measuring cup and a question: how many cups does one child drink in a day? Estimate first, measure, chart the class.
- Weigh the class bin at the end of each day for a week. Bar chart. Which day and why?
- One tank, four homes, a dry week: cubes as litres. Share it and defend the share.
- Water in, water out: a rain gauge on the sill and a line graph on the wall.
The evidence sheet
On the island, tap For teachers on the first screen, make a class (you get a six-character code and a teacher key), set the level for the class, and pick this unit as the class goal. Children join with the code and a seat number; no name, no email. The evidence sheet in the class view prints the central idea, the lines of inquiry, the concepts, what each station practised, and every seat's findings and reasons, ready to paste into your planner.
On the island
Not on the island yet: a unit on habitats and a unit on energy. Both belong to this theme and are on the list.
Read next
Explorisle is an independent product of A Surekha (the registered business of Ameera Surekha). It is not endorsed by, affiliated with or licensed by the International Baccalaureate Organization. IB, PYP and International Baccalaureate are registered trademarks of the IBO.