Unit: Fractions and Measurement

Lesson 5: Measuring to the Nearest ¼ Inch

Literature

Grade: 3

MST State Standards:

• Standard 3: Mathematics

2. Students use number sense and numeration to develop an understanding of the multiple uses of numbers in the real world, the use of numbers to communicate mathematically, and the use of numbers in the development of mathematical ideas.

• Use whole numbers and fractions to identify locations, quantify groups of objects, and measure distances.
• Use concrete materials to model numbers and number relationships for whole numbers and common fractions, including decimal fractions.

4. Students use mathematical modeling/multiple representation to provide a means of presenting, interpreting, communicating, and connecting mathematical information and relationships.

o Construct tables, charts, and graphs to display and analyze real-world data.

o Use multiple representations (simulations, manipulative materials, pictures, and diagrams) as tools to explain the operation of everyday procedures.

5. Students use measurements in both metric and English measure to provide a major link between the abstractions of the mathematics and the real world in order to describe and compare objects and data.

o Students understand that measurements are approximate, never exact.

o Students select appropriate standard and nonstandard measurement tools in measurement activities.

o Students estimate and find measures such as length, perimeter, area, and volume using both nonstandard and standard units.

o Students collect and display data.

Objectives: SWBA to…

• Read and use a ruler.
• Measure length to the nearest ½ and nearest ¼ inch.

Aim:

• If measurement is not exact, how can we measure to the nearest ½ inch and nearest ¼ inch?

Materials:

• Inchworm and a Half by Elinor J. Pinczes
• Enlarged teacher ruler
• Smartboard/chalkboard
• Sets of 5 colored strips of paper, each a different length
• Rulers
• Practice worksheet

Assessment:

• The teacher will informally assess students while he or she walks around the room observing students while working and measuring with the rulers.
• Students will also be assessed based on their measurements for each colored piece of paper measured.

Procedure:

1. Most students should already have some idea on how to measure and use a ruler to the nearest inch. As an introduction to measuring quarter inches, the teacher will read the book Inchworm and a Half by Elinor J. Pinczes while students are seated in the reading area. While reading, the teacher will ask comprehension questions regarding the sizes of the inchworms.
2. Students will return to their desks so that the teacher can show them an enlarged ruler that she has made. The teacher will first ask the students if they can find the ½ inch and then the ¼ inch markings on the ruler. The teacher will point these out so all the students can see.
3. Using the smartboard, the teacher will draw a line of any length. He or she will then hold up the ruler against the board to measure the length of the line drawn. Students will be called upon to give the measurement. This demonstration will include a few different length lines for practice.
4. Before distributing any materials for the activity, the teacher will draw a chart on the board and have students copy it into their notebooks. The left column is the color of the strip being measured, and the right column will be filled in as the strips are being measured.

Red

Orange

Green

Blue

Pink

5. While sitting at their desks, set up as tables, the teacher will give each table a set of 5 colored strips of paper. Each individual strip is a different length, but each set of strips will be exactly the same for each table.
6. Within each table, each student will begin with a colored strip. He or she will measure it and record the number in the chart in their notebook. Once the first strip is measured, they will trade strips with someone else at their table, until each color has been measured.
7. Once all the tables are finished, the teacher will ask students to help fill in the chart on the board using the answers from their notebooks.

Key Questions:

• What does the term nearest mean?
• Where is ¼ inch on the ruler?
• Where is ½ inch on the ruler?

Adaptations for Special Need & enrichment differentiation:

• The enlarged ruler will help demonstrate the term nearest when measuring in the smartboard. It will also help students to better understand how to read the quarter inch markings on the ruler.

Follow-up Assignments:

• Students will be assigned for homework a worksheet for using rulers as additional practice. Students will have to read the length of the bars drawn above the ruler to the nearest inch, ½ inch, or ¼ inch.

Reflection and Revision:

• I was very excited for this lesson. After the demonstration students really understood the nearest ½ inch and ¼ inch. While walking around during the activity a few students needed help, but once I helped them with one strip they understood all the rest. At least this is what I thought. When I asked students to help fill in the chart, the first student I called on gave me an incorrect answer so I called on someone else. That student as well gave me an incorrect answer of a whole number. So, I provided the answer; and when I did I saw many confused faces. I decided to openly ask the students if their measurements where to the nearest ½ or ¼ inch, meaning their answers were mixed numbers. They responded “No.” I then instructed the students to go back and measure the strips again, and stressed ‘to the nearest ½ inch or nearest ¼ inch.’ I also told students to help each other, and to raise their hand if they needed my help while I continued to walk around and observe.
• As a class we went over the chart a second time. This time around I received correct responses from students for each color.
• In the future, I need to provide more practice for my students so that they understand, as well as so I know they understand.