Last week I wrote about how I use a 100 bead string as a decimal number line. If you haven't already read it, you may want to start there.

In grade 4, I have been working hard with my students on decimals and fractions. We have talked a great deal about number line models for whole numbers and fractions and done a bit of work with a decimal number line that goes from 0 to 1. Today, I wanted to make some strong connections for my students and decided to use a meter stick (actually 2 meter sticks) as a decimal number line. I find that kids need to start doing number lines on something that has a scale given. Only after they have had some experience with number lines with scale can they make the jump to an open number line.

I started by writing some lists of decimals and fractions on the board. I put them in three different colors so that we could tackle this job one step at a time. I had them start with the numbers written in green (see picture below) I put the kids into groups of 3 and had them use their base 10 pieces to build each number. Then they used scraps of paper to label the collections and put their collections in order from smallest to largest.

These are the 3 sets of numbers we started with. Kids first built and placed the green numbers followed by the blue and then finally the black. |

Part of a collection. Students labeled the collections with at least one decimal and one fraction name |

Then after the collections were built, I had each group put one of the numbers where they thought it belonged on the decimal number line. They had to show us where they put it and convince us they were right. The kids did a great job with this and it brought out a lot of great connections between fractions and decimals. Very cool!

We then moved onto the next set of numbers (the blue ones in picture 1) and built and ordered them at table groups before placing them on the number line and finally did the same with the black numbers. Check out the pictures to get a good idea of what the number line looked like

A close up of the left side of the number line (0-1) |

A close up of the right side of the number line 1-2 |

You can see some numbers in the pictures above that did not appear on the board originally. That is because we got into some extension questions. The first thing that I knew I wanted to address at this stage going into the lesson was the idea of density on the number line. So I had kids find 1.3 and 1.4 on the number line and then asked them to tell me a number that was between those two numbers on the number line.

I used the <, > symbols and words to ask kids to find a number between 1.3 and 1.4 . 1.32 was one of the numbers they identified. They also identified a few others before I asked the next questions |

Some of the numbers kids found between 1.3 and 1.4. Notice the millimeter lines are visible this close up and think about how they could help your students with thousandths. |

Looking for more ideas for modeling decimals? Check out this post about 5 different models for decimals. You can grab a great set of task cards for fourth and fifth grade decimal ideas here!

Totally pinned this on Pinterest - it was very popular! :) I want to follow your blog through the Google Friend Connect, but I don't see it on the sidebar. Am I missing it?

ReplyDeleteI will look into the Google Friend Connect thing. I am new to the world of blogging and am figuring things out slowly! Thanks for the pin!

DeleteTara

This is brilliant! I teach year six in New Zealand (equivalent to fifth grade there) and I have so many kids who would benefit from this activity!

ReplyDeleteThanks so much!

x Serena x

Magic Mistakes and MayhemHi Serena,

DeleteThanks for checking out my blog! I love finding ways to make connections for kids. This activity was so beneficial to my fourth grade students that I have repeated it for my fifth and sixth graders this week! Thanks for stopping by!

Tara

We have an interactive program that does a similar job and could be moved onto after doing it practically in this lesson. Here's the link if you're interested

ReplyDeletehttp://www.taw.org.uk/lic/itp/dec_num_line.html

Really enjoyed reading this and will try it in Sept with my new class.

What a great resource! An excellent next step. Thanks for sharing :)

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