Teaching math concepts to children begins in kindergarten with the counting of objects. Counted objects can be sorted into piles, and tally marks can be made on paper to further illustrate the counting concept. As children advance in school, graphs and charts will take this concept even further. Using pie charts is a good next step for children from counting and sorting objects. Pie charts require objects (labels) and numbers (values) of each object.
Provide an overview for the children before having them create their own pie chart by drawing your own pie chart first. Draw a circle on the chalkboard. Below the circle, write the following: parents = 2, children = 3 and pets = 1. Add three pie sections to the chart and make them the appropriate size for 2, 3 and 1. Label the sections: parents, children and pets. Add the values together for a total.
Show children how to calculate the percentage. Explain how this simplified pie chart shows how many parents, children and pets there are in relation to the whole. The numbers represent percentages that must add up to 100% to fill the chart. Discuss the reason for the labels and numbers to create the pie chart. The labels are used to identify each area of the pie. The numbers specify the percentage of each area of the pie.
Give children a piece of blank paper. Have them draw a circle on the paper as you draw one on the board. Give each student three groups of objects. Ask the students to sort the object and count them. For example, provide 10 marbles, 15 buttons and five crayons. List the items provided on the board, asking each student to copy what you write. Tell the students that the item name is the label. Ask the students how many of each object they were given. Write the total number of items next to each label and add them all together. The board and the students' papers should look like this:
Explain how to calculate the percentage of each item by taking the number of each item label divided by the total number. Write the percentages next to each label. It should look like this:
marbles 10 = 33%
buttons 15 = 50%
crayons 5 = 17%
Ask the children to write the percentages next to the count of each item as you did on the board.
Use the circle you drew on the board and show the children how to divide it based on the percentages. Draw a line down the middle explaining each half is 50%. Draw a horizontal line explaining each section is now 25%. Next, draw a new circle on the board. Show the children how to divide it based on the task they just completed with the three objects listed on their papers. Help children divide the sections of their pie chart. The student created sections will not be exact the first time they create a chart, but encourage them to do their best to make it close. The sections should be 33%, 50% and 17%. Finally, have the students label each section of the chart.