DS2 is 3.2. He has a significant speech delay, which he has had 2 sessions of SALT for. He has also had numerous hearing tests, which showed him to have glue ear until February this year (aged 2.10). He has also been receiving 2-year funding for nursery for about 8 months & has an IEP at nursery. He attends around 18 hours per week over 2 days. SALT also said that he had a very short attention span & delayed pretend play skills, which was probably linked to his speech delay.
His speech has improved greatly over the last 3 months. In this time he has gone from saying around 30 words to saying hundreds (too many to count) & using sentences of up to 5 words. His attention span has also increased & whereas he would find it hard to sit through half a 30 minute activity with me or at nursery, now he will sit through the whole thing. His pretend play skills are also improving & whereas before he would eg play with a toy kitchen by opening the oven doors a lot & putting things in there, now he will pretend to make & eat food, bring it to me, pretend to wash up etc.
One area that has also improved but seems further behind than other areas is his understanding. He does not always follow or understand what is said to him (about 70% of the time for instructions). Also, if you ask him a question eg how was nursery, he will just look at you & not respond. He does not yet nod his head or say yes, but he will use 'no' quite a lot. We went to a theme park at the weekend & when asked how a ride was he would say 'nice' so I think he is starting to improve.
I just wondered if anybody has any advice on how to help improve his understanding? I worry that he will struggle at school (due to start in September 2015) if he can't understand what is being asked of him 
I am kind of hoping it will just come on, like his speech has, but I want to do what I can to help him in the meantime.