Actors often pretend to chew toffees and recite the months of the year backwards with their tongues hanging out before they go on stage.

And such vocal warm-up techniques can be adapted by teachers to help primary pupils develop their voices. Youngsters will be more confident about speaking in class or assembly as a result, and they will learn voice and breathing skills that should benefit them across the curriculum. They will also project their voices more effectively, speak at the right pace and deliver words clearly and with expression.

Simply through opening their mouths wider when talking, and speaking with upward and downward inflections, pupils can banish monotonous or muffled voices.

Drama games can be effective in making pupils more aware of their voices and how they can disguise them. Get one pupil to sit on a chair with their back to the class. Another says: “I’m here, great master” in a different voice or accent and the master must guess who said it.

Tongue twisters devised by pupils are ideal for helping them practise their speaking. Where the tongue is placed in the mouth determines how every sound is uttered. Get the class to try a “l-l-l” sound and then a “r-r-r” and notice how the tongue is in a different place each time.

At St James’ Infant School in Tunbridge Wells, Kent, Melanie Shackleton, deputy headteacher, encourages the use of actors’ voice techniques. “I have noticed that some of the quieter children are now more confident to speak up,” she says. “It has given pupils a better understanding of all subjects. Once they have spoken the words - whether in literacy, science or history - they find it easier to write them, or at least try.”

Like actors, pupils with good breath control will not strain their voices and can calm their nerves before speaking in front of others or beginning work.

The secret is to breathe using the diaphragm muscle and not the chest so that you inhale as much air as possible.

Actors love to chant mantras when practising breathing. Repeating phrases such as “I am calm” or “I can do this” will also help pupils relax and concentrate if they are finding a particular piece of work difficult.

Lucy Morgans, an actress and drama teacher at Croham Hurst School, a fee-paying school in Croydon, recommends that pupils pretend they are blowing away dandelion seeds. Another option is to take a deep breath and see how far through the alphabet children can get before needing to breathe again.

“You can also ask children to pant like a dog, which really gets the diaphragm working,” she says

Steve Hemsley is co-author of Boost Your Child’s Confidence published by Infinite Ideas on April 18.

SPEAKING PROPER

- Introduce an actor’s vocal warm-up before a lesson to help pupils concentrate and focus on breathing.

- Pupils can locate their diaphragm by putting a thumb on their last rib and placing a hand on the bottom of their stomach. If the shoulders move they’re breathing incorrectly.

- Make pupils aware of their voices by recording them reading text as different characters and playing it back to them.

- Help pupils appreciate different voice volumes by saying words quietly or loudly on a scale of one to five.