The Danish toy maker is testing a way for customers to ship their unwanted bricks back and get them into the hands of other kids.

It says US customers can print out a mailing label on its website, dump their used Lego bricks in a box and ship them off at no charge.

The pieces will be cleaned, put in a box and given to Teach for America, a non-profit that will donate them to classrooms across the United States.

Some bricks will be also sent to the Boys & Girls Clubs of Boston for their after-school programs.

If the test is successful, Lego might expand the program beyond the United States in 2020.

Lego's vice-president of environmental responsibility, Tim Brooks, said on Tuesday the company typically told its customers to keep their bricks or pass them on to others but some had asked for another way to donate them.

Lego, like other big brands, is looking to please customers worried about plastic's impact on the environment.

Brooks said Lego was also working to find other materials for its bricks but finding one as durable as plastic had been a challenge.

In 2018, however, it began making Lego trees and bushes out of sugar cane.

Rival Hasbro, which makes Monopoly and Mr Potato Head, said it planned to eliminate plastic use in its packaging by 2022.

Australian Associated Press