Logic and Proof

November 20, 2019

Puzzles: Introducing KenKen Puzzles

This page focuses on a way to introduce KenKen puzzles so that students see, focus on, and learn the logic, not just guessing. These puzzles give […]
November 21, 2019

Measurement: Discovering formulas for area

Area formulas Students who have the informal notion that area is the “amount of 2-D ‘stuff'” contained inside a region can invent for themselves most of […]
November 21, 2019

Puzzles: Who Am I Puzzles

Who-Am-I? puzzles give clues about some mathematical object — usually a number or a shape — and you are to figure out what the object is. […]
November 21, 2019

Puzzles: KenKen Puzzles

KenKen(R) puzzles were not built into Think Math! but are a wonderful material to make regularly available to children. These puzzles give excellent arithmetic practice while […]
November 21, 2019


This article deals with the meaning of multiplication, how it is introduced in Think Math!, and the early acquisition of facts.
December 3, 2019

Difference of Squares

This page describes one silent teaching activity that serves, at the superficial level, to give students useful practice with multiplication facts, but that also builds deeper […]
December 3, 2019

Puzzles: Logic Puzzles

Logic puzzles are used as basic exercises not only in mathematics but in law. The Law School Admission Test (LSAT) is full of logical puzzles, and […]