Mary Ellen
Kanthack
BROOKWOOD MIDDLE,
GENOA CITY,
WI

4th Grade Math :
Unit #6 - Fractions 1: Understanding Equivalence in Fractions and Decimals :
Lesson #11

Objective:
SWBAT compare and plot decimals on a number line, explain equivalency of decimals, and convert decimals to fractions.

1 Warm Up: Human Decimal Number Line -
10 minutes

To get our minds wrapped around our quiz, I wanted to do an activity that would stir up their thought process on comparing decimals. I gave each student a number card that had decimals written on them. Their goal was to get themselves ordered from least to greatest correctly.

I started by having them flip their card over to look at the decimal number. I told them that I wanted them to form a number line with their cards at the back of the room from least to greatest going left to right, just like a number line. I set the timer and they got going! Collaboration

There was noise, rushing around, checking, comparing and discussions and disccovery!We all have 21! Students approached me when they were figuring out three of them had the same decimals. They couldn't believe they were right. Finally, our number line came together in a matter of 3 minutes. Getting it together!

I asked them why they were able to get it together so fast? One student replied that it's because they "get decimals now!"

resources

Collaboration.mov

https://betterlesson.com/lesson/resource/2883005/collaboration
Getting it together!.mov

https://betterlesson.com/lesson/resource/2883007/getting-it-together
We all have 21.mov

https://betterlesson.com/lesson/resource/2883008/we-all-have-21
2 Quiz Time! -
25 minutes

I wrote this quiz to assess three things:

1) I want to assess their ability to compare and plot decimal numbers on the number line.

2) I want to see if they can explain the value of similar looking decimal numbers using tenths and hundredths. I try to include a writing and explanation component to every quiz and test because CCSS aligned state tests will expect this and I think it is just best practice to expect students to explain their reasoning.

3) I want them to show me that they can write decimal numbers as fractions.

I passed the quiz out and went over directions carefully, realizing that I had written the third standard incorrectly. I corrected myself and explained the expectation that they needed to show conversions of decimal to fractions in tenths and hundredths. ( Your resource is correct. The quiz is thirteen points total. Numbers one and two are worth 2 points each.)

Students wrote this quiz in about 20 minutes.

resources

Quiz 2 Decimals.pdf

https://betterlesson.com/lesson/resource/2882993/quiz-2-decimals
A Clear Understanding

Quizzes

In this Educreations video, I show you some writing samples of the explanation comparing .8 and .08. For the most part, students really did a good job using the words tenths and hundredths to compare the differences between them. They also explained that 8 tenths was larger. I saw some varied understanding of comparison of fractions and bringing the tenths out to hundredths to compare and therefore making some foolish errors. i.e # 3 .79 to .9, the students didn't bring the .9 out to .90 to compare, yet did it on # 5 when comparing .06 and .6. Therefore many said that .79 was larger than .90. That may have to do with understanding the "how" and not the "why" we would bring out the tenth to the hundredth place. They are looking at it as a process when the numbers are the same: . 6 . 06. It's just a hunch, and based on what I understand about my student's minds and that as we transition to CCSS, I have to continually battle the " I just want to know how to do it," frame of mind.