Fractions

Designed by: Christi Jones and Jeanna Hoffman
Satchel Ford Elementary School

Core Curriculum Objective:  Identify, name and demonstrate fractional parts of a set or region using a variety of manipulatives and pictures (e.g., equal versus unequal parts of a whole, wholes, halves, thirds, fourths, fifths, sixths, eighths, and tenths).  Write the corresponding fractions and order them correctly.  (2NR5-1)

Grade level: Second       Subject:  Math

Overview:  Students will view a pattern block web site.  Students will learn about part versus whole using a hexagon.  Students will use pattern blocks to demonstrate fractional parts of a hexagon.  Students will make construction paper hamburgers using circle fractions.  Students will choose which fractional parts they want for their hamburger and write the fraction that corresponds. 

Focus Question:  How can we show a fraction?

4)  Time Frame:  2 lessons (60 minutes each)

5) Resources/ Materials:  

pattern blocks (class set)

http://www.best.com/~ejad/java/patterns/patterns_j.shtml

overhead pattern blocks

construction paper

glue

die cut circles for each student

*2 light brown

*1 dark brown

*1 red

*1 yellow

*1 white

"1/3" fraction die cut circles

*light green

"1/6" fraction die cut circles

*dark green

portable dry erase boards

dry erase pens

white paper (large)

6) Culminating Assessment:  Students will create a construction paper hamburger using circle fractions.  See directions in activity two.

*When correcting the hamburgers, look at the shape the student cut out and see if the fraction he or she wrote is correct.

7)  Instructional Activities: 

Activity One:

Tell the students that today they are going to learn about fractions.  Have students view the pattern block web site http://www.best.com/~ejad/java/patterns/patterns_j.shtml .  Show the students a hexagon.  Tell them that it is a whole hexagon.  Drag a trapezoid and place on top of the hexagon.  Explain that a trapezoid is one half of the hexagon.  Write 1/2 on a dry erase board and show the children.  Explain that the bottom number of the fraction means how many parts in all and the top number means how many parts of the whole.

Cover the hexagon with two trapezoids and show how two trapezoids equal one hexagon. 

Drag another hexagon on the grid.  Drag a triangle on top of the hexagon and tell the students you want to find out how many triangles fit on a hexagon.  Continue dragging over triangles until it is covered.  Ask the students how many triangles it took to cover the hexagon----6.  Take 5 triangles off and write a fraction (with the students help) for the remaining triangle-1/6.  Drag another triangle on top of the hexagon and write the fraction on the dry erase board---2/6.  Continue until the hexagon is covered.

Give the students a set of pattern blocks, a dry erase board and a pen.  One bucket of 250 pattern blocks is usually enough for a table of four students.  Use the overhead pattern blocks to teach this lesson.  Ask students to find a trapezoid.  Ask them to find a shape that would equal 1/3 of the trapezoid----triangle (write one third on the overhead).  Place a triangle on top of the trapezoid.  Ask them to find another triangle and place it on the trapezoid.  Write a fraction for two triangles-2/3.  Have the students write the fraction on their dry erase board.   After doing a couple more examples, collect the pattern blocks and boards.  To close, review what a fraction is and how to write one.  Ask the students why we use fractions.

Activity Two

Pass out the dry erase boards again.  Use the overhead pattern blocks and place shapes on the screen.  Have the students write the corresponding fraction on their dry erase board to review the previous lesson.  Have them hold their boards in the air.  The teacher should observe to see if the students understand the concept.  Give feedback when necessary. 

8) Culminating Assessment:

Tell the children that they are going to  make hamburgers using fractions.  Give each student a big white piece of paper, one of each die cut circle (except 2 light brown).  Tell the students that the light brown pieces are the buns.  Show the students how to place one bun at the top of their paper and one at the bottom.  Explain that the whole dark brown circle is the meat.  Place that on top of the bottom bun. 

Tell the students that the red is ketchup, yellow is mustard, white is onions, light green is lettuce and dark green is pickle.  Tell the students that you like mustard.  Fold the yellow circle in half and explain that since you like mustard you are going to fold it in half (a big fraction).  Tell the students that your second favorite item is lettuce.  Show the students how the light green circle is cut in thirds.  Tell the students that next you like ketchup.  Fold the red circle in fourths and point out the difference in the fractions so far.  Tell the students that the dark green circle is pickle and that you aren't too crazy about them.  Show them how to fold into sixths.  Last, tell the students that your least favorite item is onions.  Fold the white circle in eighths and point out the difference in all the circles. 

Put your hamburger together by cutting one part of each item and placing it on your hamburger.  As you place an item on the hamburger, write the corresponding fraction next to it on the paper.  For example, the onion was folded in eighths.  Cut 1/8 of the onion and after placing it on the hamburger, write 1/8 next to it.  Do this for all the items until you are finished making your hamburger. 

Tell the students they have to fold each item differently.  They have to use all of the following fractions:  1/2, 1/3, 1/4, 1/6, and 1/8.  Then they may decide how much of each item they want, cut it out, place it on the hamburger (any way they want) and write the corresponding fraction.  The children have to use all of the items.  Even if they raise their hands and say they don't like mustard, they still have to use it.  Tell them they may want to use less of an item they don't like and more of an item they like. 

Once complete, ask some students to choose a partner and share their hamburgers.  Give feedback to each student while walking around and observing.  Ask the students to glue their hamburger to the paper.  Collect the hamburgers and grade them using the rubric.  Display the hamburgers in the library for others to enjoy.

To close, ask the students why fractions are important and how they might use them in the future.  Tell them that they will use fractions when cooking.  Ask them to imagine long ago when there weren't any measuring cups.  Ask how they cooked back then?  Tell them that now we have measuring cups with the fractions on there to help us cook.