1. Grade 4 Video Outcomes
N4.4 Demonstrate an understanding of multiplication of whole numbers (2- or 3-digit by
1 – digit) by:
modeling the distributive property
using personal strategies for multiplication, with and without concrete materials
using arrays to represent multiplication
connecting concrete representations to symbolic representations
estimating products
solving problems
Synopsis
Clip 4.4A models the 2006 Census problem presented below using Base 10 blocks to
represent the Stockholm population if it grew by three times its 2006 population. The left
to right algorithm is presented as follows:
323 Answer: Stockholm’s population would be 969.
x 3
900 (3 x 300) Students should be encouraged to solve questions like this in a
60 (3 x 20) number of different ways including but not limited to using the
traditional right to left algorithm with carrying. Wherever possible
+ 9 (3 x 3) multiplication and division should be presented as related
969 operations
Clip 4.4B models and discusses a 2 by 4 or 4 by 2 array of cubes on a square centimetre
grid and a 13 by 3 or 3 by 13 array as well as the related division questions 39/3= 13 and
39/13=3. The clip also suggests using square centimetre paper to construct various arrays
as a way of determining unknown facts using known facts. For instance an 8x 7 array
can be divided into an 8 x 3 array and an 8 x 4 array (24 + 32= 56).
Problem
According to the 2006 Census, Stockholm had a population of 323. If Stockholm were to
grow to three times its 2006 population what would its population be?
Concrete Manipulatives: Base 10 ones, tens and hundreds, square centimetre overlay
grid, and square centimetre paper.
Virtual Manipulatives
1
