Curated OER
Five by Two
Help young mathematicians read and interpret numbers from 1 to 10 and sequence them correctly with this card game. Using a deck of cards and two to three classmates, have one player hand out ten cards to each gamer and then put the extra...
Illustrative Mathematics
The Napping House
How many people and animals can cram into a single bed? Find out with this cross-curricular math and language arts lesson. Following along with a reading of the children's book The Napping House by Audrey Wood, young mathematicians...
Illustrative Mathematics
Kiri's Mathematics Match Game
Learning math is so much more fun when it involves playing games. Following the rules of the classic game Memory, young mathematicians flip over two cards at a time as they look for numbers whose sum or difference is equal to the value...
Illustrative Mathematics
Counting Squares
Challenge young mathematicians' understanding of squares with this geometry puzzle. The task is simple, identify as many squares as possible in a 3x3 array. Allow learners to work independently or in pairs as they search for squares,...
Illustrative Mathematics
Comparing Products
How can 5th graders show understanding that 30 x 225 is half of 60 x 225 without completing the computation? They can use an area model and draw it out. An array, or an open array, is an area model that allows for young learners to...
Curated OER
Shapes and Their Insides
Learners follow a series of instructions for drawing and coloring different shapes in order to learn the difference between the perimeter and area of a polygon. Then they are asked to find the perimeter and area of a 3x4 rectangular...
Curated OER
Halves, Thirds, and Sixths
An excellent activity that effectively pulls together the concepts of area, fractions, and equivalent fractions! Using 3x2 rectangular arrays, 3rd graders are introduced to the concept of area in terms of square units. Building on this...
Illustrative Mathematics
“One More” Concentration
Help your primary learners develop an understanding of the concept of one more and one less using two sets of number cards. The first set of cards, all in one color, is the "one less" deck. The second set, again all in one specific...
Illustrative Mathematics
“Crossing the Decade” Concentration
Young mathematicians concentrate on learning to fluently count. Following the rules of the classic game Memory, children take turns flipping over cards in order to find pairs of numbers that cross a decade (e.g. 29 and 30). For younger...
Curated OER
Connor and Makayla Discuss Multiplication
The commutative property of multiplication applies not only to whole numbers but to fractions as well. Connor and Makayla explore and discuss the idea that 2/3 x 3 is the same as 3 x 2/3. Your 5th grade class will connect with...
Curated OER
Measure the Gardens
Understanding arrays is very similar to understanding the relationship between multiplication and area. Give your third graders an opportunity to practice identifying area models that relate repeated addition and multiplication. They...
Illustrative Mathematics
Summer Swimming
Here is a real-world application for systems of equations. When is it better to pay an enrollment fee and lower daily rate, and when is it better to pay the regular price? The local swim center is having a special offer, reductions in...
Curated OER
A Tour of Jaffa
Use the age-old Traveling Salesman Problem to introduce Hamilton circuits to your young travelers. Individuals then plan an efficient route to visit all the places they want to go.
Curated OER
Choosing a College
How can mathematics help scholars choose a college? High schoolers learn how they can use decision matrices to rank colleges based on selected criteria. They also see how to weigh criteria using multiplication of the decision matrix by a...
OnlineMathLearning.com
Online Math Learning: Addition and Arrays (Grade 2)
A list of suggested activities for addressing CCSS 2.OA.C.4 where students work with arrays and repeated addition. Includes a problem for a 3X5 array and its solution in a video. [8:23]
K-5 Math Teaching Resources
K 5 Math Teaching Resources: Multiplication Arrays [Pdf]
Practice multiplication by two, three, four and five.
University of Cambridge
University of Cambridge: Nrich: Napier's Bones
Use this one page website to learn how to multiply and divide a "new" way. This method was invented over 400 years ago by John Napier. A detailed explanation is only a click away.