I highly recommend watching this documentary film which is available currently on Netflix.
It's about a boy with SEN, including illiteracy, and his experience in a mainstream school over two years.
It brought tears to my eyes. It was great to see how much progress he made in small group teaching, but sad that his difficulties in class meant him eventually being excluded from the school, and there was not much information given as to what happened to him following this.
It's heartbreaking that this boy could have done really well with ongoing intense intervention, but that the barrier to this is funding. It seemed at the end that the school gave up on him, as he just spent time in the nursery.
I would be curious to hear others views.