How to Measure the Ocean

By Inda Ahmad Zahri

Review by Zewlan Moor

Inda Ahmad Zahri is an author, illustrator, surgical doctor and scuba diver. She was inspired to create this book when her daughter said, ‘What I love about numbers is that they go on and on and on forever.’

Recently I heard someone say that the concepts in How to Measure the Ocean were too difficult for the preschool and lower primary age group. I seethed, and couldn’t stop myself from calling out, “Why do we underestimate our children?” This is a book that encourages and extends the child reader.

Children explore volume though water play, and counting and categorising through sorting their beloved collections, every day.  This book can be read at many levels in the present, and revisited over time, as a child’s conceptual framework expands.

From the cover, this picture book is intriguing. The title raises questions. How do we measure the ocean? What sort of book is this? A non-fiction exploration of mathematics? A kids’-own ocean adventure? The cover composition encourages the reader’s eye to travel down the yellow measuring tape, as if the children are reeling in the corner of the book, to help lever it open.

The first double spread is encouraging in its simplicity. The illustration shows adults sitting on a beach watching children wade in the ocean shallows. The text is brief and unintimidating: “The ocean can be difficult to measure.”

Zahri then guides the reader through concepts of mass, volume and quantity. These are couched in child-friendly examples, such as:“You can’t lift it onto scales to see how heavy it is.”

“You might be able to scoop it out, cup by cup . . . / . . . but you’d need a very big bucket to calculate its volume.”

“Oceans are often easy to spot. Easy to name and easy to count. / But there are half-oceans. Almost-oceans. Once-oceans.”

This last example demonstrates Zahri’s seamless transition into geography and history, a cross-curricular approach that will be valuable in schools.

Other “lessons”, on the water cycle, discoverabilty, education and resilience, are interspersed throughout the book. Two double spreads warrant particular mention. The first needs to be rotated clockwise to view vertically. It features a number line, a concept explored in the primary school mathematics curriculum. This number line is of the depths of the ocean in metres. The animals found at various depths are illustrated along the number line, from tropical fish near the surface to ghost fish in the depths.

The second spread features Zahri’s cursive handwriting on grid paper. Detailed pencil drawings of shells are superimposed, with the resultant effect reminiscent of Da Vinci’s notebooks. The philosophical notes, about the mathematics of the Fibonacci sequence and Pythagoras’ triangle, are ambitious but will appeal to some readers. Of note are the depictions of trade and value. Two boys ponder their seashells, “sand dollars”, and “what you could get for a fistful.” The reflection, “No monarch’s face, no heads, no tails, just mathematics” could be read as a critique of colonialism and the division of the world into binaries.

There is a neat twist near the end of the book, which further expands the meaning of the text. By the end, we are asking, “How do we measure the immeasurable?”

Allen and Unwin 2024

Inda Ahmad Zahri

Zewlan Moor is the author of Nothing Alike and The Bill Dup. She is also a doctor and friend of Inda Ahmad Zahri