How to Create
Bar and Line
Graphs
Draw and label the Axis
Y – Axis
X - Axis
Identify and label
variables
Y – Axis
Dependent
Variable
(what is being
observed)
X - Axis
Independent
Variable
(what is being
changed by scientist)
Helpful Hint: DRY MIX
D.R.Y.
D – Dependent
R – Responding
Y – Y axis
M.I.X.
M – Manipulated
I – Independent
X – X axis
Scale and Intervals
• Decide on an appropriate
scale
• Minimum and maximum numbers used
on each axis. May not start with zero
• Numbers used should be a little below
the lowest value and a little higher than
the highest value
• Use common and consistent intervals
Scale = 0 to 70
Intervals of 10
Title and labels
• Place an appropriate and descriptive
title at the top of your graph
• Label the Y and X axis with their
variables (X with the independent
variable and Y with the dependent
variable
Bar Graphs
• Compare groups by showing relative amounts
(totals) or categories
Line Graphs
• Show relationship between the independent and
dependent variable
• Used to show trends and make predictions
Line Graphs can be used to
show multiple sets of data
Slugs were fed a variety of foods to determine
their feeding preferences. Based on the data
given, construct the appropriate graph and
formulate a conclusion.
Food Source
Food Eaten (grams)
Lettuce
4.0
Mushrooms
8.2
Dog food
0.0
Spinach
6.5
Apple
8.6
Peach
5.4
Orange
1.0
Slugs Favorite Food
Grams Eaten
10
9
8
7
6
5
4
3
2
1
0
Grams Eaten
Every ten years scientists counted the number of 3
endangered birds to see if their conservation efforts
were working. Review the data table, construct the
appropriate graph and formulate a conclusion.
Bird Species
Whooping
Crane
California
Condor
Black Swan
1950
1960
1970
24
41
78
76
46
20
56
58
57
Endangered Bird
Populations
90
80
Number
of Birds
70
60
50
Whooping Crane
40
California Condor
30
Black Swan
20
10
0
1950
1960
Years
1970