Skill: Create line graphs

A line graph shows how a measured amount changes in an order, such as from day to day.

Example

A student counts the number of birds seen each day:

Day	Birds seen
Monday	2
Tuesday	4
Wednesday	3
Thursday	5
Friday	6

Step 1: Draw and label the axes

• Draw a horizontal axis for the ordered input: Days.
• Draw a vertical axis for the measured amount: Number of birds.
• Put the days from left to right in order: Monday, Tuesday, Wednesday, Thursday, Friday.

Step 2: Choose an even scale

The vertical axis should have equal spaces for equal amounts. Use a scale counting by $1$:

$$0,\ 1,\ 2,\ 3,\ 4,\ 5,\ 6$$

Do not make some spaces larger or smaller than others.

Step 3: Plot each point

Pair each day with its number of birds:

• Monday: $(\text{Monday}, 2)$
• Tuesday: $(\text{Tuesday}, 4)$
• Wednesday: $(\text{Wednesday}, 3)$
• Thursday: $(\text{Thursday}, 5)$
• Friday: $(\text{Friday}, 6)$

For example, the Monday point goes above Monday and across from $2$ on the vertical axis.

Step 4: Connect the points

Connect neighboring points with straight line segments:

• Connect Monday to Tuesday.
• Connect Tuesday to Wednesday.
• Continue until Friday.

The line goes up when the number increases and down when the number decreases.

Step 5: Read the graph

From the data:

• The number of birds increased from Monday to Tuesday.
• It decreased from Tuesday to Wednesday.
• It increased from Wednesday through Friday.
• Friday had the greatest number of birds: $6$.

The points represent the actual days observed. The connecting lines show the pattern from one observation to the next; they do not necessarily tell the exact number of birds on times between those days.