It could be a selection of books or magazines on topics that learners are interested in, written in English.
Example
A classroom library can include readers, the teacher's own books, and books lent by learners.
In the classroom
Ways to encourage learners to use a class library include practising sub-skills such as guessing meaning from context, guiding learners in their selection of material, and giving learners the opportunity to share their thoughts and reactions to books through discussions and mini-presentations.
Further links:
https://www.teachingenglish.org.uk/article/teaching-reading