learning and teaching idioms

You can learn idioms through pictures:
Jay Doubleyou: idioms of the world

Here's a great lesson plan - getting students to illustrate idioms:
Learning Idioms in ESL : Lesson Plans : Vocabulary.com

You can learn idioms through cartoons:
Jay Doubleyou: a symphony in slang: a classic cartoon full of idioms

This is for beginners/children:
Everyday Idioms - made easy - YouTube

You can learn idioms through stories and story-telling:
A Story FULL OF IDIOMS - Would you like to try finding them ;) - EnglishClub

There are also lots of lists of idioms:
Idioms: Introduction
ESL - English Idioms

But you need lots of activities to make sense of them and to bring them alive.
This is an excellent and very practical guide:

The Role of Illustrations in Reading
> words and pictures presented together helped students recall better

Group Discussion in Reading Comprehension
> ESL students engaging in collaborative talk during content reading, they assisted one another in understanding the meaning of challenging words, getting the main ideas, and answering questions about what they read.

Retelling in Reading
> students in pairs to retell the content in their own words instead of the English idioms and to rewrite sentences provided in class by using English idioms.

Dialogue Writing and Role-play in Reading
> dialogue writing could motivate students to write without burden because of pair collaboration and role-play activity could help them remember the dialogue they wrote through repetitive practices.

Wu - Effective Activities for Teaching English Idioms to EFL Learners (TESL/TEFL)
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