Bruce Ramsey:

Sally made 500 gingerbread men. She sold 3/4 of them and gave away 2/5 of the remainder. How many did she give away?
This was one of the homework questions in Craig Parsley’s fifth-grade class. The kids are showing their answers on the overhead projector. They are in a fun mood, using class nicknames. First up is “Crackle,” a boy. The class hears from “Caveman,” “Annapurna,” “Shortcut” and “Fred,” a girl.
Each has drawn a ruler with segments labeled by number — on the problem above, “3/4,” “2/5” and “500.” Below the ruler is some arithmetic and an answer.
“Who has this as a single mathematical expression? Who has the guts?” Parsley asks. No one, yet — but they will.
This is not the way math is taught in other Seattle public schools. It is Singapore Math, adopted from the Asian city-state whose kids test at the top of the world. Since the 2007-08 year, Singapore Math has been taught at Schmitz Park Elementary in West Seattle — and only there in the district.
In the war over school math — in which a judge recently ordered Seattle Public Schools to redo its choice of high-school math — Schmitz Park is a redoubt or, it hopes, a beachhead. North Beach is a redoubt for Saxon Math, a traditional program. Both schools have permission to be different. The rest of the district’s elementary schools use Everyday Math, a curriculum influenced by the constructivist or reform methods.

Related: Math Forum Audio / Video.