Lea puts a finger against her lips while classmates are talking. What message is she sending?

Carlo waves as a visitor leaves. What message is he sending?

Partners understand the same hand signal differently. What should they do before using it again?

A hand signal always means the same thing in every country.

Ana's friend can see her but cannot hear her. How can Ana send a message?

What must pupils learn to tell whether a school bell means recess or class?

What message does an ambulance siren send to nearby drivers?

What two kinds of beeps does Morse code combine?

How does a Morse code chart help someone read a message?

What instrument is known as the 'talking gongs' of Mindanao?

How can players make gong messages resemble speech?

What does a red traffic light tell a driver?

In Morse code, what does a brief signal-lamp flash represent?

Why do boat crews check a lighthouse's flashing pattern?

Why were signal fires placed on hills or towers?

Which condition makes smoke signals hardest to read from far away?

What carries messages through fiber-optic cables?

Pupils cannot see a hand signal from the back. What change would help?

Mina raises her arm while ringing a bell. What two ways is she using to send information?

During signal practice, how can classmates check that a message was understood?