Monday

Rocket slaps a clipboard onto the Numbers Desk. "Field Day is three weeks away. I need to know how many games to build."

"So ask the kids on our street," Raven says. "How many games would you play?"

Rocket grabs a marker. "Easy. Everyone will say five. Five games. Done."

Nova hovers over the clipboard, her light blinking. "Will everyone give the same answer?"

Rocket pauses. "Well, no. Some kids get tired. Some want to play all day."

"Then one answer is not enough," Raven says. "We need all of them. What do you notice about that?"

Rocket grins. "It is a question with many answers. That means we need data."

Nova dims her light. "And data needs a picture. Start collecting."

Some questions have one answer. "How many legs does a chair have?" You can look at the chair and know.

A statistical question is different. It expects different answers from different people or different measurements.

"How many Field Day games would the kids on our street play?" Some kids will say 3. Some will say 7.

Because the answers vary, you collect them all. That collection is your data. Then you look at the whole set at once.

A good statistical question says who you will ask and what you will count. "How many minutes do kids on our street read each night?"

It names the group (kids on our street) and the measure (minutes of reading). Both parts matter when you report the answer.

Raven tried the question on 12 kids first, to practice. She wrote each answer on the tally sheet, never the kid's name.

Nova turned the list into a dot plot. Each dot is one kid. A dot sits above the number that kid said.

Look at the plot. The dots pile up in the middle and thin out at the ends. That pile is the shape of the data.

The tallest stack is at 4. The answers reach from 3 to 7. Nobody said 8 or more.

Good start. Tomorrow you learn two ways to draw a data set: the dot plot and the histogram.