Engage -
The teacher will engage the students in a discussion of the number line. The teacher will remind the students that they have already studied many number lines, including number lines counting by 1's, 2's, 5's, and 10's. The teacher will display the number line KWL chart and the students will receive their own number line KWL chart to fill in together. The teacher will ask students what they know about number lines and what they want to know about number lines. The group will fill in the first two sections of the number line KWL chart. Then, the teacher will lead students in a choral count by 1's to 10, 2's to 20, 5's to 50, and 10's to 100, to encourage participation and instill confidence in these skills they have already mastered (the teacher will use the number line generator found in the materials section to generate the number lines the students are chorally counting by and will display these for all to see on the document camera, while the students are chorally counting). The teacher will then "shift gears" and lead the students in a discussion of fractions, by examining a ruler and completing the first two sections of the fractions KWL chart. The teacher will ask the students measure their pencils with rulers, using inches. The teacher will demonstrate that not all pencils will have a whole number measurement. Some pencils will lie in between the whole numbers. The teacher will point out the "tick marks" that lie between the whole numbers. These are fractional portions of inches! Next, the teacher and students will complete the fractions KWL chart. Then, the teacher will then ask the key question of this lesson, "Where do fractions go on the number line?" This question is important because it is the main focus of this lesson and it will show how the two KWL charts are related.
*Evaluate - Teacher will assess students understanding of fractions and number lines via KWL charts, confirming and correcting as needed.
Explore -
The teacher will encourage students to make predictions, about where fractions should be placed on a number line labeled to "1". The students are then given a blank fraction number line sheet and are partnered with their shoulder partner. The teacher will write "1/2" on the board and will ask the students to place 1/2 on the first number line (the students will place fractions on the number line much like normal digits; a small line (tick mark) crossing the number line, with the fraction written underneath the tick mark). The students at this point may or may not know where some of the fractions will lie on the number line. The teacher will write the following fractions one at a time and will ask the partnered students to place the fractions on the corresponding number lines (second line - 1/3...2/3, third number line - 1/4...2/4...3/4, fourth number line - 1/6...2/6...3/6...4/6...5/6, fifth number line - 1/8...2/8...3/8...4/8...5/8...6/8...7/8)
*Evaluate - The teacher will observe the students' work, listening to conversations about where the fractions will lie on the number lines. The teacher will neither confirm nor deny student work at this point.
Explain -
The Teacher will now distribute one copy of Black Line Fraction Strips per pair. The teacher will ask the students how they did with their blank number lines. The teacher will listen to students as they describe fractions they labeled correctly and incorrectly. The teacher will state that as fractions are labeled, it's important to remember that these fractions are equal parts of the whole. The teacher will demonstrate (using the document camera) how the fraction pieces are equal (1/2 = two equal pieces, 1/3 = three equal pieces, 1/4 = four equal pieces, etc). The teacher will state that the denominator represents how many equal pieces are on the number line, while the numerator represents a certain piece on the line.
*Evaluate - The teacher will listen to student comments about the placement of fractions and will lead a discussion about fractions that were easy or hard to place.
Extend -
The teacher will now explain that the students will be working in centers. In the first center (majority of the students), shoulder-partnered students will use chart paper to create a poster of fractions on number lines. A number line will need to be created for each of the fraction sets (denominators 2-10). See Fractions on the Number Line Poster Rubric (in attachments) for poster grading guidelines. The second center will be computer stations in which shoulder-partnered pairs will complete Internet activities listed in the Extensions section. Students will be given a 45 minute block of time to complete the poster. Students will spend 15 minutes on the computer activities. The rotating strategy and timeline for the two centers will depend on how many students are involved and how many computers are available.
*Evaluate - Students are evaluated on posters created based on the Fractions on the Number Line Poster Rubric.