Search Results for: lattice

Showing v. Telling: Lattice Continued

That last post wasn’t really about the lattice algorithm. This one isn’t either. It’s about supporting claims with evidence. (The last one, in case you’re keeping score, was about crafting tasks that show instead of spiels that tell). Another claim … Continue reading

Place value and the Lattice Algorithm (or A Simple Task, Years in the Making)

I’m going to assume you know the lattice algorithm for multidigit multiplication. If you do not, and if you would like a primer, here is one. This post isn’t really about the lattice algorithm, but it’s the context for what … Continue reading

Standard algorithms unteach place value

I found a page full of computations sitting around the house this evening. Naturally, I picked it up and gave it a look. Griffin (10 years old, 5th grade) had been doing some multiplication in class today. Somehow his scratch … Continue reading

What is “the standard algorithm”? [#algorithmchat]

Richard Skemp wrote, in “Relational Understanding and Instrumental Understanding,” about faux amis—those pesky words in other languages that look like words you are familiar with, but which mean something else entirely. Skemp argues that the word understand is like this—different people use it to … Continue reading

Diagrams, week 10 (bonus)

A former calculus student who is tutoring in a local elementary school stopped by to ask about how and why decimal points work in the lattice algorithm for multi digit multiplication. Here’s the residue of our conversation.