Island area

Overview

Using this Resource

Connecting to the Curriculum

Marking Student Responses

Working with Students

Further Resources

This task is about estimating area.

Use this map of Motunui and Ririki Islands to help you answer the following questions.

Question 2Change answer

a) Describe fully how you could estimate the area of the islands.

b) Using your method above, estimate the area of the islands.

i) Motunui Island km²

ii) Ririki Island km²

Task administration:

This task can be completed with pen and paper or online (with NO auto marking).

Level:

Curriculum info:

Keywords:

Description of task:

Students estimate (and explain how) the area of two islands on a grid.

Curriculum Links:

This resource can help to identify students' understanding of calculating perimeter and area and multiplicative strategies.

Learning Progression Frameworks

This resource can provide evidence of learning associated with

within the Mathematics Learning Progressions Frameworks.

Answers/responses:

			Y8 (05/1998)
a)		Count squares and part-squares filled by .5 or more. or Count whole squares. Put part squares together to form whole squares. or Make into composite shapes that are approximately the same area as the island. NOTE: Must be more extensive than just 'count the squares'.	difficult
b)	i) ii)	Motunui 49.5 km² – approx. [Accept 46-53.] Ririki 19.5 km² – approx. [Accept 16-23.]	difficult difficult

Diagnostic and formative information:

	Student response	Likely reason
b) i) ii)	66 (approximately) 31 (approximately)	Counts number of squares where any part of the island is in.
b) i) ii)	27 (approximately) 25 (approximately)	Confuses area and perimeter.