MHB How Can a Third Grader Identify Marks on a Number Line?

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To identify marks on a number line, a third grader can determine what each mark represents by counting the divisions between whole numbers. For example, if there is one mark between each pair of whole numbers, it indicates a fraction, such as 1/2. The Common Core Standards introduce fractions in third grade, making this a relevant topic for students at that level. Understanding how to represent fractions on a number line is part of the curriculum, which supports the idea that third graders can grasp this concept. Overall, with proper instruction, third graders should be able to identify and understand marks on a number line.
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Third Grade Math QuestionHow can you find what each mark represents on a number line? How does a 3rd grader answer that?

It is hard thinking like a third grader.

Here is my attempt:How can you find what each mark represents on a number line?

By counting the number of marks between each pair of whole numbers.

I drew a number line here. In this number line, there is one mark between each pair of whole numbers. Each mark must shows 1/2.

0--|--1--|--2--|--3--|--4--|-->

Is this an answer that a third grader would give?
 
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In what grade are fractions, and, in particular, 1/2, normally introduced?

Added: the "common core" introduces fractions in the third grade. So, yes, this is a reasonable third grade question.
 
HallsofIvy said:
In what grade are fractions, and, in particular, 1/2, normally introduced?

Added: the "common core" introduces fractions in the third grade. So, yes, this is a reasonable third grade question.

Fractions are normally introduced in 5th grade unless it is an advanced third grade class. How would you answer this question as a third grader?
 
A search reveals that as HallsofIvy stated, fractions are introduced to students in the third grade according to the Common Core Standards, where they are taught (among other things):

1. Understand a fraction 1/b as the quantity formed by 1 part when a whole is partitioned into b equal parts; understand a fraction a/b as the quantity formed by a parts of size 1/b.

2. Understand a fraction as a number on the number line; represent fractions on a number line diagram.

a. Represent a fraction 1/b on a number line diagram by defining the interval from 0 to 1 as the whole and partitioning it into b equal parts. Recognize that each part has size 1/b and that the endpoint of the part based at 0 locates the number 1/b on the number line.

b. Represent a fraction a/b on a number line diagram by marking off a lengths 1/b from 0. Recognize that the resulting interval has size a/b and that its endpoint locates the number a/b on the number line.​

If those points are taught and grasped by the student, I see no reason why a third grader couldn't understand what each mark on a number line represents. :)
 
RTCNTC said:
Fractions are normally introduced in 5th grade unless it is an advanced third grade class. How would you answer this question as a third grader?
Well, when I was a third grader I would have answered "Uh, what?"
 
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