Tag Archives: mental math addition

Teaching Addition and Subtraction in Grades 2 & 3

Happy New Year, Everyone!

2and 3 cover

I am pleased to announce the release of my latest resource,  Sums and Differences – Teaching Addition and Subtraction in Grades 2&3.  This teacher resource is matched to the WNCP curriculum and addresses the operations of addition and subtraction  to 100 for grade 2 and to 100o for grade 3.  Designed to be used by teachers of combined grades – or by anyone who has a range of learners in their classrooms – these lesson sequences focus on the big math ideas of adding and subtracting!  Each lesson asks students to engage with place value in concrete, pictorial and abstract ways, while practicing and developing fluency with the operations.  Word problems, games and written practice are included to ensure students hone their skills and deepen their understanding of addition and subtraction with bigger numbers.

The resource includes all the line masters, game boards, written practice and teaching materials required to support your students in becoming proficient with addition and subtraction in ways that are consistent with the curriculum and which promote number sense.

This 220 page resource is just $40 plus shipping. Click here to order!

PS – The companion resource for grades 1&2 is also available for purchase. Read about it by clicking here.

PPS – My sincere apologies.  I have discovered 2 errors in the book. One comes on page 167, in the game called “Three in a Line – Subtracting hundreds, tens and ones”.  The wheel at the top of the page and the differences below don’t match. 😦  I’ve attached the replacement game here for you.

Three in a line HTO game NEW

Likewise, I’ve had some feedback about the “I have…, Who has…?” game in the early pages of the resource.  I’ve re-created it and uploaded the replacement here.

“I have, who has” game NEW

Thanks for your patience and understanding…



Deep Sea Duel – A mental math and logic game for all

I discovered this engaging game a week or so ago and wanted to share.  It’s called Deep Sea Duel. In the game, you match wits with the computer in the form of an octopus called Okta.  (She’s the same character as in the iPad game called Pick-a-Path, below).  When you square off against Okta, you can choose the level of difficulty and her level of “nastiness”.  Good thing too.  It took me a while to sort out a strategy for winning when things were too easy, and I had to crank up the nastiness in order to really understand the game and its complexity. The thing that I hadn’t considered was that Okta could win with ANY of her 3 (4) cards – not just the first 3 – if that makes any sense. 😛

The goal of the game is to reach a target number by adding a set of cards together. You and Okta take turns. As you play, keep track of both your score and Okta’s to be able to block her attempts to collect three (or 4) cards with the specified total before you can!  There’s a ton of mental math going on in this game – and, if you’re up for it, you can move into decimal numbers too…!!

Enjoy…!  More games and links like these can be found on the NCTM Illuminations webpage.