Global Explorers: Our Changing World · 6th Class · Mapping the World · Spring Term

Grid References and Location

Practice using four-figure and six-figure grid references to precisely locate features on Ordnance Survey maps.

• NCCA Curriculum Specifications
• NCCA: Primary - Maps, Globes and Graph Work
• NCCA: Primary - Using Maps

About This Topic

The Global Grid is the invisible system of latitude and longitude that allows us to pinpoint any location on Earth. In this topic, 6th Class students learn about the Equator, the Prime Meridian, and how time zones are calculated. They explore the historical significance of Greenwich and why a standardized system is essential for global trade, aviation, and communication. This topic meets NCCA standards for understanding the Earth and the Universe and develops essential mathematical and geographic skills.

Students also examine how latitude affects climate and culture, linking the physical position of a country to the daily lives of its people. Understanding the global grid is key to grasping how our world is interconnected. Students grasp this concept faster through structured discussion and peer explanation using globes and physical models.

Key Questions

1. Explain the system of grid references used on Ordnance Survey maps.
2. Differentiate between four-figure and six-figure grid references in terms of precision.
3. Justify the importance of accurate grid references in emergency situations.

Learning Objectives

• Calculate four-figure grid references for given locations on an Ordnance Survey map.
• Determine six-figure grid references for specific features with greater precision.
• Compare the level of detail provided by four-figure versus six-figure grid references.
• Explain the systematic method used to derive grid references from map coordinates.
• Justify the critical role of precise grid references in coordinating emergency services.

Before You Start

Introduction to Maps and Symbols

Why: Students need to be familiar with basic map elements and the concept of representing real-world features symbolically before learning to locate them.

Cardinal Directions and Compass Points

Why: Understanding North, South, East, and West is fundamental to interpreting the Eastings and Northings that form the basis of grid references.

Key Vocabulary

Grid Reference	A system of lines on a map that creates a grid, used to identify precise locations.
Eastings	Vertical lines on a map that are numbered from west to east, indicating distance across the map.
Northings	Horizontal lines on a map that are numbered from south to north, indicating distance up the map.
Four-figure Grid Reference	A grid reference using the Easting and Northing numbers of the grid square a feature is located within.
Six-figure Grid Reference	A grid reference that adds a further digit to both the Easting and Northing to pinpoint a location within a grid square.

Watch Out for These Misconceptions

Common Misconception

Latitude and longitude lines are actually visible on the Earth.

What to Teach Instead

Younger students might think these are real lines. Using a globe and a flashlight, show that these are human-made 'imaginary' lines used for measurement, much like the inches on a ruler don't exist on the object being measured.

Common Misconception

It is always the same time everywhere in a single country.

What to Teach Instead

Students in Ireland (a single time zone) often assume this is true for everyone. Using a map of the USA, Russia, or Australia helps them see that large countries span multiple time zones, requiring active calculation when calling across the country.

Active Learning Ideas

Simulation Game: The Time Zone Challenge

Students are given 'flight times' and must calculate what time it is in different cities (London, New York, Tokyo) when they land. They use a physical time zone map and a clock face to move forward or backward across the Prime Meridian.

40 min·Pairs

Inquiry Circle: Battleship Coordinates

Using a world map with a latitude and longitude overlay, students play a game where they must 'sink' ships by calling out precise coordinates. This reinforces the 'North/South, East/West' naming convention for coordinates.

30 min·Pairs

Think-Pair-Share: Latitude and Lifestyle

Pairs are given two different latitudes (e.g., 60°N and 0°). They must brainstorm how life would differ in those places regarding clothing, housing, and food, then share their ideas with the class to see the link between grid position and climate.

25 min·Pairs

Real-World Connections

• Search and rescue teams, like mountain rescue volunteers in Snowdonia, use six-figure grid references to pinpoint the exact location of a lost hiker or an accident site, ensuring rapid response.
• Delivery drivers and logistics companies use grid references, often alongside GPS coordinates, to navigate to specific addresses or drop-off points efficiently, especially in rural or undeveloped areas.
• Cartographers and surveyors use detailed grid systems to create accurate maps and record precise measurements for construction projects or land management.

Assessment Ideas

Quick Check

Provide students with a section of an Ordnance Survey map. Ask them to identify and write down the four-figure grid reference for a named village and the six-figure grid reference for a specific landmark, like a church or a trig point.

Discussion Prompt

Pose the scenario: 'Imagine you need to report a wildfire. Why is giving a six-figure grid reference more helpful to the fire brigade than a four-figure grid reference? What information might be lost if you only gave the four-figure reference?'

Exit Ticket

Give each student a card with a feature marked on a small map snippet. Ask them to write the six-figure grid reference for that feature and then explain in one sentence why this level of precision is important for locating it.

Frequently Asked Questions

Why is the Prime Meridian in Greenwich, London?

In 1884, an international conference chose Greenwich as the Prime Meridian (0° longitude) because at the time, most of the world's ships already used charts based on it. It was a practical decision for global navigation that we still use today.

What is the difference between latitude and longitude?

Latitude lines run horizontally (like the rungs of a ladder) and measure how far North or South you are from the Equator. Longitude lines run vertically (long-ways) and measure how far East or West you are from the Prime Meridian.

How many time zones are there in the world?

There are 24 main time zones, one for every hour in a day. Each time zone is roughly 15 degrees of longitude wide. However, some countries adjust their time zones for political or geographical reasons, so the lines on a map often zigzag!

How can active learning help students understand the global grid?

Active learning, such as 'Coordinate Battleship' or physical role-playing of time zone changes, removes the abstraction. When students have to 'travel' across the grid to solve a puzzle, they internalize the logic of the system much more effectively than by just looking at a static map.