Making abstract entities into characters with their own looks and personalities is a great idea related to many traditions. “Flatland” featured creatures embodying shapes in different dimensions.

More recently, moe anthropomorphisms embody entities such as Wikipedia:

The book “What’s unnatural” by Jeremiah Dyke of Hands on Math has a cute anthropomorphic numeral 1 as its main character. The images overall have peaceful, slow and steady feel to them, which I like a lot.

The character goes through different number lands, largely corresponding to the extension of numbers from natural to real. It’s a useful topic, and representing it spatially makes a lot of sense, given the traditional Venn diagrams showing relationships among numbers.

Here are things I would change in the next version of the book.

Show number properties rather than telling about them. It’s done beautifully for negatives, but not for other number types.

I was concerned about negatives presented as “positive numbers that carry a bar.” A negative number is a single entity, even though it takes two symbols to represent it. The same goes for fractions represented as “numbers chopped into pieces” – a fraction is a number in its own right, a single number at that. This seems like a minor point, but kids get confused around this issue.

I would continue to the land of reals rather than irrationals, because it breaks the previous pattern. Natural-whole-rational-… is the previous adventure, and the next in line seems real, not irrational.

I would use the book with kids for its roleplaying potential, and the strength of its overall travel metaphor. Thank you for making it!