Data and Graphs
Learn how to collect, organize, and show data using tables and graphs.
Learn
When scientists do investigations, they collect data. Data are facts and numbers you gather. But a bunch of numbers can be confusing. That is why we organize data in tables and show it with graphs!
What is Data?
Data is information you collect during an investigation. Data can be:
- Numbers: The plant grew 3 inches. The temperature was 72 degrees.
- Observations: The ice melted completely. The ball bounced to the red line.
- Counts: 5 students chose vanilla. 8 students chose chocolate.
Data Tables
A data table organizes your information in rows and columns. It makes data easy to read.
Example: Plant Height Over Time
| Day | Plant A Height (inches) | Plant B Height (inches) |
|---|---|---|
| Day 1 | 2 | 2 |
| Day 4 | 3 | 4 |
| Day 7 | 5 | 6 |
| Day 10 | 6 | 9 |
Types of Graphs
Graphs are pictures that show data. Different graphs are good for different kinds of data.
Bar Graphs
Bar graphs use bars to compare amounts. The taller the bar, the bigger the number.
- Good for comparing groups (favorite colors, types of animals)
- Each bar represents one category
- Read the height of the bar to find the number
Picture Graphs (Pictographs)
Picture graphs use small pictures or symbols to show data.
- Each picture stands for a certain number (like 1 or 2)
- Count the pictures to find the total
- Fun and easy to read!
Line Graphs
Line graphs show how something changes over time.
- Points are connected by lines
- Good for showing growth, temperature changes, or anything that changes
- Read left to right to see the change
Parts of a Graph
Every graph needs:
- Title: What the graph is about
- Labels: What each axis (side) shows
- Numbers or scale: How to read the amounts
- Key (for picture graphs): What each picture means
Examples
Example 1: Reading a Bar Graph
Graph Title: Favorite Fruits in Our Class
The bar graph shows: Apples (8 students), Bananas (5 students), Oranges (7 students), Grapes (4 students)
Questions to answer:
- Which fruit is most popular? Apples (tallest bar)
- Which fruit is least popular? Grapes (shortest bar)
- How many more students chose apples than bananas? 3 more (8 - 5 = 3)
Example 2: Reading a Picture Graph
Graph Title: Books We Read This Month
Key: Each book picture = 2 books
- Week 1: 3 book pictures = 6 books
- Week 2: 4 book pictures = 8 books
- Week 3: 2 book pictures = 4 books
- Week 4: 5 book pictures = 10 books
Total books read: 6 + 8 + 4 + 10 = 28 books
Example 3: Making a Data Table
Sara measured the temperature outside for 5 days. Here are her measurements: Monday 68F, Tuesday 72F, Wednesday 70F, Thursday 65F, Friday 74F
Data Table:
| Day | Temperature (F) |
|---|---|
| Monday | 68 |
| Tuesday | 72 |
| Wednesday | 70 |
| Thursday | 65 |
| Friday | 74 |
Coldest day: Thursday (65F) | Warmest day: Friday (74F)
Practice
Answer these questions about data and graphs.
1. What is data?
Show Answer
B) Information you collect - Data includes numbers, observations, and counts from your investigation.
2. A bar graph shows: Red (6), Blue (9), Green (4), Yellow (8). Which color has the most votes?
Show Answer
B) Blue - Blue has 9, which is the highest number.
3. In a picture graph, each star picture = 3 stickers. If you see 4 stars, how many stickers is that?
Show Answer
C) 12 - Each star = 3 stickers, so 4 stars = 4 x 3 = 12 stickers.
4. Which type of graph is best for showing how a plant grows taller over many days?
Show Answer
C) Line graph - Line graphs are best for showing change over time.
5. What does every graph need?
Show Answer
B) A title - Every graph needs a title to show what it is about.
6. Look at this data: Monday - 5 birds, Tuesday - 8 birds, Wednesday - 3 birds. How many total birds were seen?
Show Answer
C) 16 - Add them up: 5 + 8 + 3 = 16 birds.
7. A data table has rows and columns. What do the rows and columns help you do?
Show Answer
B) Organize information - Tables help keep data neat and easy to read.
8. In a picture graph, there are 6 apple pictures. The key says each apple = 2. How many apples total?
Show Answer
D) 12 - 6 pictures x 2 = 12 apples.
9. Which graph uses bars to compare different groups?
Show Answer
B) Bar graph - Bar graphs use bars of different heights to compare amounts.
10. Sam measured the temperature: 9 AM was 60F, 12 PM was 75F, 3 PM was 78F, 6 PM was 70F. When was it warmest?
Show Answer
C) 3 PM - 78F is the highest temperature in the data.
11. Why do scientists make graphs?
Show Answer
C) To show data in a picture that is easy to understand - Graphs help us see patterns and compare data quickly.
12. A bar graph shows how many pets students have: Dogs (12), Cats (9), Fish (6), Birds (3). How many more dogs than cats?
Show Answer
A) 3 more - 12 - 9 = 3 more dogs than cats.
Check Your Understanding
Challenge 1: You count how many cars pass your house in one hour for 4 days. Monday: 15 cars, Tuesday: 22 cars, Wednesday: 18 cars, Thursday: 10 cars. Create a data table with this information. Which day had the most cars? The least?
Show Sample Answer
Data Table:
| Day | Cars Counted |
|---|---|
| Monday | 15 |
| Tuesday | 22 |
| Wednesday | 18 |
| Thursday | 10 |
Most cars: Tuesday (22 cars)
Least cars: Thursday (10 cars)
Challenge 2: Explain the difference between a bar graph and a line graph. When would you use each one?
Show Sample Answer
Bar Graph: Uses bars to compare different groups or categories. Use it when you want to compare separate things, like favorite colors or types of animals.
Line Graph: Uses dots connected by lines to show change over time. Use it when you want to show how something changes, like temperature during a day or plant height over weeks.
Next Steps
- Practice reading different types of graphs
- Try making your own data table and graph at home
- Move on to the next lesson: CER Writing