Scatter plots and lines of fit – Grade 11 math lesson

Lesson 22 of 23 in the Grade 11 math course

US version. US grades, US spelling and dollars ($). · UK Maths Department

A complete 45-minute lesson for grade 11 (ages 16–17) that runs on this page – at school or at home. Every answer is graded right away, with a worked explanation.

Time: 45 minutes + 20 min homework
Grade: Grade 11 (ages 16–17)
You need: Paper, a pencil and this page
Graded: Instantly, with explanations

For parents: how to use this lesson

You don't need to know this topic yourself. The lesson explains each step on screen, one tidy step at a time. Every answer is graded straight away with a worked explanation, so you never have to grade anything.

Read what your child will learn and the big ideas together.
Press Start the lesson below and sit with your child for the teaching and the worked examples (about 19 minutes).
Let them do the practice on their own. They choose Getting started, On track or Challenge – start on On track and move up after a few right in a row.
Finish with the exit ticket and the talk question: “Does a link between two things mean one causes the other? Think of an example.”
Later that day or the next day: the homework (20 minutes), then a practice test.

Watch out for

Joining the points dot to dot. Draw one straight line through the middle of the points.
Saying correlation means one causes the other. Ice-cream sales and sunburn rise together because of sunny weather.

Tip for home: Talk about whether taller people have bigger feet, and test it.

What your child will learn

Learning goal: plot and interpret scatter plots and use lines of fit.

Success looks like

I can plot a scatter graph.
I can describe correlation.
I can use a line of best fit to estimate.

Key words

correlation: a relationship between two variables
line of fit: a straight line through the middle of the points
outlier: a point far from the pattern
interpolate: estimate within the range of the data

What to have ready

Paper and a pencil
This page on a computer, tablet or phone
For the hands-on part: Measure hand spans and heights of family members and plot them on a scatter graph.

The big ideas (for the adult)

A scatter graph plots pairs of values to see if they are related.

Positive correlation: as one goes up, so does the other. Negative: as one goes up, the other goes down. No correlation: no pattern.

A line of fit follows the trend of the points. Use it to estimate, but only within the range of the data. Correlation does not prove one thing causes the other.

The lesson, step by step

45 minutes in 5 parts
Part	Time	How it is checked
Starter: quick recall	5 min	Graded by Classfern
Teaching input	10 min	Not assessed, self-checked
Worked examples and guided practice	9 min	Not assessed, graded by Classfern
Independent practice	15 min	Graded by Classfern
Closure and exit ticket	6 min	Graded by Classfern, self-checked

Starter, "your turn", practice and exit ticket are graded by Classfern. Worked examples and teaching are not assessed. The hands-on task and the reflection are self-assessed. Explanations in talk are judged by the parent and not recorded.

The lesson

It runs here on the page. No sign-up and no names – progress is kept only in this browser.

Homework and practice at home

20 minutes: 10 practice questions, 3 multiple-choice questions and 2 to remember from earlier work, then a short reflection. New questions every time, all graded instantly.

More practice

All Grade 11 math lessons and tests · Math Department

Curriculum

Common Core State Standards HSS.ID.C.8: “Compute (using technology) and interpret the correlation coefficient of a linear fit.”

Common Core State Standards HSS.ID.C.9: “Distinguish between correlation and causation.”

Our lessons and questions are our own. They are not written or endorsed by any government department, testing agency or exam board.