JL my dss suffered from glue ear from his toddler years up until he was a teenager.
It affected his education at an early stage because the school were unaware he had hearing difficulties. The problems that developed with communication and his behaviour then unfortunately blighted his time at school (oterh factors contributed too but fundamentally I think his poor start affected his entire education, really).
He had repeated sets of grommets which I suppose helped a bit, otehr options (such as dietary changes) were not considered - but if it was DS now, I would definitely try cutting out dairy etc.
Dss always drunk loads of milk and it may be anecdotal but I'm sure it didn;t help.
He also changed schools several times which hindered him and despite repeated requests - and promises of additonal help, from boht his secondary schools, this was never forthcoming. Basically I don;t think anyone realised that he was actually quite deaf a lot of the time, and his lack of concentration etc was down to the fact that he simply tuned out because he couldn;t hear evry well.
By teh time he was a teenager attitude problems had set in which made the whole situation very difficult to sort out.
he left school with very poor GCSE grades despite being a bright and resourceful lad.
A cautionary tale - make sure you get the help he needs from school, GP, anyone involved, now.
And yes, do point out to people that he can;t hear very well.