Straw trick

Overview

Connecting to the Curriculum

Marking Student Responses

This task is about investigating water and gravity.

Instructions

Suck some water up the straw.
Quickly put your finger over the top end and hold the straw upright over the bowl of water.
Take your finger off the top of the straw and see what happens.

Question 1Change answer

a) What happened to the water in the straw, when your finger was held over the top of the straw?

b) What happened to the water in the straw, when you took your finger off the top of the straw?

c) Give a reason for what happened when you took your finger off the top of the straw.

Level:

Curriculum info:

Keywords:

Description of task:

Students carry out and make observations about water in a straw, and suction. Students are then required to explain their observations.

Curriculum Links:

Science capabilities

The capabilities focus is brought about by the conversations you have and the questions you ask.

Capability: Gather and interpret data

This resource provides opportunities to discuss how inferences are derived from observations.

Science capabilities:

Making Better Sense:

Answers/responses:

a)	i) ii)	The water stays in the straw when it is covered by a finger. The water runs out of the straw when the finger is removed.
b)		Explanation that mentions air pressure, e.g., no air can get to the top of the straw to force the water out, therefore it stays in the straw. or When the finger is removed the pressure of the air pushes the water down the straw and it is replaced by air.