For Parents

Why We Refuse to Sell Anxiety

“Don't let your child lose at the starting line” is a sales pitch, not a truth. This is momomori's first stance — and my bottom line for every product I make.

Subtraction Isn't 10−7. Subtraction Is Knocking Down Your Tower.

Kids aren't incapable of grasping the abstract — the abstract just has to become something they can touch, play with, and win at first. This is momomori's second principle: concrete before abstract.

“One More Round”: The Early Signal of Self-Directed Learning

I don't measure how many problems a child gets right. I measure whether, after one round, they say those four words on their own.

Reading Isn't a Task — It's a Door You Can Push Open

When reading is turned into a checklist, it dies. What I'd rather do is let a child discover there's something behind the door.

From Trader to Dad: Everything I Learned About a Sense of Probability

Trading taught me to live with uncertainty. I'm more and more convinced it's the ability kids should get earliest — and are taught least.

Does NumWar's Core Loop Hold Up?

Hypothesis · Yes. Rock-paper-scissors gives fair tension, knocking down the tower turns subtraction into a visible thrill, the three-way choice provides strategic tension, and short, comeback-friendly rounds lower the barrier to “one more round.”

Key metric · Spontaneous “one more round” rate R ≥ 50%

Independent Bath Training: Turning a Chore Into a Game

Hypothesis · Yes. When something shifts from “being told to do it” to “clearing my own levels,” the child's resistance disappears — because the motivation moves from external to internal.

Key metric · Over 7 consecutive days, an unprompted self-completion rate ≥ 70%

A Sense of Time: Making “5 Minutes” Something You Can Touch

Hypothesis · Yes. Map abstract duration onto a concrete, visible physical change (sand, light, a progress bar), and a child can build the intuition “this long = this much.”

Key metric · Without looking at a clock, estimate “5 minutes” with an error < 50%