Measuring length – Grade 1 math lesson
Lesson 13 of 15 in the Grade 1 math course
US version. US grades, US spelling and dollars ($). · UK Maths Department
A complete 45-minute lesson for grade 1 (ages 6–7) that runs on this page – at school or at home. Every answer is graded right away, with a worked explanation.
- Time
- 45 minutes + 15 min homework
- Grade
- Grade 1 (ages 6–7)
- 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: “Why does it matter where you start measuring on the ruler?”
- Later that day or the next day: the homework (15 minutes), then a practice test.
Watch out for
- Starting a measurement at 1 or at the end of the ruler. Put the 0 mark at one end of the object.
- Thinking a bigger object is always heavier. Check with a balance: a pillow is big but light.
Tip for home: Measure and weigh ingredients when cooking together.
What your child will learn
Learning goal: compare and measure length, mass and capacity using the right units.
Success looks like
- I can compare lengths, masses and capacities.
- I can measure with a ruler from 0.
- I can choose a sensible unit.
Key words
- length
- how long something is
- mass
- how heavy something is
- capacity
- how much a container holds
- unit
- what we measure in, such as cm or kg
What to have ready
- Paper and a pencil
- This page on a computer, tablet or phone
- For the hands-on part: Measure toys with a ruler, weigh fruit on kitchen scales, and fill jugs with water to compare capacity. No rulers? Use hand spans or cubes to measure instead.
The big ideas (for the adult)
To compare, line things up from the same starting point, or use a balance to see which is heavier.
To measure length with a ruler, start at 0, not at the end of the ruler.
Choose a sensible unit: centimeters or meters for length, grams or kilograms for mass, milliliters or liters for capacity.
The lesson, step by step
| 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
15 minutes: 8 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
More Grade 1 math lessons
- Numbers in words
- Comparing numbers
- Addition facts to 10 and 20
- Adding and subtracting
- The equals sign and missing numbers
- Addition and subtraction word problems
- Skip counting
- One more, one less, ten more and ten less
- Tens and ones
- Number lines
- Recognizing fractions
- Telling time
- Picture graphs and bar graphs
- Shapes and position
Curriculum
Common Core State Standards 1.MD.A.1: “Order three objects by length; compare the lengths of two objects indirectly by using a third object.”
Common Core State Standards 1.MD.A.2: “Express the length of an object as a whole number of length units, by laying multiple copies of a shorter object (the length unit) end to end; understand that the length measurement of an object is the number of same-size length units that span it with no gaps or overlaps. Limit to contexts where the object being measured is spanned by a whole number of length units with no gaps or overlaps.”
Our lessons and questions are our own. They are not written or endorsed by any government department, testing agency or exam board.