Topic: Geographic grid and cartographic grids

Author: Magdalena Jankun

Target group

Students of the 6th grade of elementary school.

The topic includes content that goes beyond the core curriculum

Core curriculum

VI Geographical coordinates: latitude and longitude; mathematical and geographical location of points and areas.

Student:

1. reads the latitude and longitude of selected points on the globe and on the map;

2. on the basis of given geographical coordinates indicates the location of points and areas on the maps at various scales;

3. marks the coordinates of any points in the field (using a map or GPS).

The general aim of education

The students indicate the differences between a geographic grid and a cartographic grid.

Criteria of success

• You will know the system of meridians and parallels on the globe and on the map;

• you will distinguish a geographic grid from a cartographic grid;

• You will recognize the types of cartographic grids and give their examples.

Key competences

• communication in the mother tongue;

• communication in a foreign language;

• mathematical competences;

• digital competence;

• learning to learn;

• social and civic competences.

Methods / forms of work

Work with text and work with multimedia, conversation, brainstorming method.

Individual work and work in pairs.

Teaching aids

• abstract;

• interactive whiteboard;

• multimedia projector;

• tablets/computers;

• inductive globe;

• geographical atlases.

Lesson plan overview (Process)

Introduction

1. The teacher presents the topic, lesson goal and criteria of success.

2. The teacher initiates brainstorming by asking the students if they know the difference between a geographic grid and a cartographic grid.

3. The teacher instructs the students to read a fragment of the abstract explaining the meaning of both terms. The students indicated by the teacher define them on the class forum.

Realization

1. The teacher uses an inductive globe and draws the system of meridians and parallels. The teacher emphasizes that the geographic grid is a conventional system of meridians and parallels on the surface of the globe or on its model called a globe.

2. The teacher gives geographical atlases to the students. The students’ task is to carefully look at the meridians and the parallels on the map of world and on the map depicting Antarctica, and then give the characteristics of both cartographic grids.

3. The teacher asks the students about the cause of a different layout of meridians and parallels on both maps. The students submit this problem to discussion.

4. The teacher explains that the method of presenting the geographic grid on the plane is called cartographic projection. Based on the illustration in the abstract, the teacher discusses three main types of projections, which are distinguished due to the way the projection surface is applied:

• azimuthal (planar) projection;

• conical projection;

• cylindrical projection.

The teacher asks the students to draw attention to the shape of the meridians and the parallels, and to the surface of the lands in each of the projections.

5. The students independently do an interactive exercise consisting in creating a map of jigsaw puzzles and determining the type of its projection. The teacher corrects mistakes, if any.

6. The students work in pairs, search for maps that have azimuthal, conical and cylindrical grids.

Summary

1. The teacher displays two exercises on the interactive board:

• checking the ability to distinguish types of cartographic projection (matching the map to the type of projection);

• consolidating the knowledge gained during the lesson (filling gaps in the text summarizing the most important information).

The exercises are done on the class forum by volunteers or students indicated by the teacher.

2. The teacher assesses the students' work during the classes, taking into account their activity and individual possibilities.

The following terms and recordings will be used during this lesson

Terms

Texts and recordings

Geographic grid and cartographic grids

The geographic grid is a conventional system of meridians and parallels on surface of the Earth or its model, called the globe, and the cartographic grid is its equivalent on a plane. One of primary tasks of cartography, in scientific terms, was inventing a way to attain seemingly impossible – to “flatten” a spherical surface (or its section) so that it would precisely adhere to a plane. Cartographers developed mathematical and optical methods aiming to tackle this task. These methods are called map projections.

The easiest way to comprehend what map projection is involves imagining a glass sphere with plotted geographic grid and a glowing light bulb inside. Such arrangement would make meridians and parallels cast their shadows on a flat surface, wrapped around such sphere, thus creating a cartographic grid.
There are three basic categories of map projections, with regard to a way of application of a plane to project on:

• azimuthal projection;

• conic projection;

• cylindrical projection;

• conventional projection (a modification of the aforementioned types according to determined mathematical assumptions in order to achieve faithful projection of angles, surface or distance).