Grade 3: Number Sense & Numeration Big Ideas

Bonjour! Here is a little rundown of some of our big ideas for Number Sense & Numeration this year in Math. Number Sense and Numeration is broken down into three 'families' of concepts: Quantity Relationships, Counting, and Operation Sense. 

Quantity Relationships means comparing numbers, putting numbers in the correct order, reading and writing number words, understanding the value of a digit in a multi-digit number (for example, what does the 3 in 435 represent?), composing and decomposing numbers (ie show me how to build 435 using 100-blocks, 10-blocks, and 1's blocks, or how many 100's are in 435?, etc), rounding numbers to the nearest 10, estimating, ideas of one half/one quarter/a third (we don't use the notation yet). 

Counting in grade 3 includes counting to 1,000 by 1's, 2's, 5's, 10's, 100's (I like to do 25's as well), from various (friendly) starting points - for example I wouldn't ask our students to start at 7 and count up by 25's, but I would ask them to start from 425 and count up by 25's to 1,000; and counting backwards by 2's, 5's, 10's from 100 using 'friendly' starting points (ie multiples of 2 if its by 2, multiples of 5 if it's by 5, etc, although by 10's can start from any number), and down by 100's from 1,000 or any number less than 1,000 (similar to counting down by 10's - you can start anywhere). 

Operational Sense is what most people would say 'math' is. In grade 3, we will solve problems using addition and subtraction of two-digit numbers using mental strategies; add and subtract three-digit numbers using concrete materials, student-generated algorithms, and standard algorithms (the traditional 'carry the 1' method); estimate the answer to judge if our calculation is reasonable; discuss real-world applications for one-digit multiplication and dividing by one digit numbers; multiply to 7x7 (I'm hoping we will do up to 10x10) and divide to 49/7 using a variety of strategies. 

These expectations are what is to be learned by the end of the year. I will keep you posted on what we are working on currently so you can practice along at home.