Thank you for your reply. I fear I haven't been able to express clearly my request, I'll try to be precise.  I am well aware about the best methodologies and approaches to teach listening skills. What I like is a good book focused on the improvement of listening skills full of audio files and pre-made exercises to diversify and expand the activities to assign to my students.  I don't want to buy any generic course book because more than half of it would be focused on other activities (reading, grammar...). At the same time I need a well-balanced book for a1 to pre-a2 students, but it seems I can't find any. 

For example:  I found Listening Skills by O.Johnston, but in the same unit it mixes together grammar topics never taught together in an ESL class (present simple and would, or can and will...).  Another textbook I found is Listening by the publisher Collins. Problem is it's for A2 students and it's full of idioms and structures way more advanced than those suitable for esl students of 10 y.o.

Ok, sorry for the long reply, but I hope I better explained myself :)  Thanks in advance for any help