A teachers' organization in Philadelphia is encouraging teachers to wear Black Lives Matter T-shirts and provide lessons on the movement every day for one week.

Amy Roat of the Caucus of Working Educators tells radio station KYW that the group is urging participating teachers to let principals know of their plans for the week of Jan. 23 and isn't encouraging anyone to be insubordinate.

It's not known how many teachers will take part.

A school district spokesman would say only that the district provides regular avenues for students to learn and express themselves. The main teachers union hasn't taken a formal position.

The Black Lives Matter movement largely emerged after high-profile killings of unarmed black men and boys by police. It now has a broader racial justice agenda.