The SEN Code of Practice which came into effect on 1 September 2014 requires schools to provide appropriate support so that all children have the opportunity to benefit from an inclusive education. A dyslexic child should be offered differentiated support to address the child’s particular learning needs. Dyslexia is a recognised difficulty under the Equality Act 2010.
Look at the School Information Report and SEN Policy as they will inform you as to the schools intervention and assessment processes. The Report and Policy can be used to discus your concerns with the SENCo at the school.