Meet the character
Meet Reti the Yeti
Reti the Yeti is the friendly hero of Reti the Yeti: Adventures in Sumtopia, the screen-free math story and workbook from Supernova Kids. Kids join Reti on a snowy adventure and learn their addition and subtraction facts through 10 along the way — about ten minutes at a time, with a pencil instead of a tablet.
Who is Reti the Yeti?
Reti is a warm, slightly clumsy, endlessly determined yeti who lives in Sumtopia — a snowy world where math holds everything together. Reti's name comes from the phrase every child in the story learns to say out loud: "Not yet." Not "I can't." Not "I'm bad at math." Just not yet — because the fact you don't know today is simply one you haven't practiced enough times.
That is why Reti exists. Children who believe they are bad at math stop trying. Children who believe they just haven't learned it yet keep going. Reti is the character who makes that mindset feel like an adventure instead of a lecture.
Adventures in Sumtopia
The first Reti the Yeti book is an interactive math story and workbook for ages 5–9, covering addition and subtraction facts through 10.
- A story kids follow — help Reti save Sumtopia
- Facts taught directly and in order, not randomly drilled
- Short, winnable pages that end on a high note
- Free printable Reti flashcards included with the book
What kids learn with Reti
Addition through 10
Every fact introduced in a deliberate order, with a strategy for each family of facts.
Subtraction through 10
Taught as the flip side of addition so kids see the connection instead of memorizing twice.
"Not yet" confidence
Short pages kids can finish build the belief that they can get better with practice.
Want more of the teaching behind the character? Read How Reti the Yeti teaches math facts in The Launchpad, or meet Sabrina, the teacher who created him.