I taught in an international school in Gran Canaria, Spain for 8 years. Almost very child was Spanish and they received a curriculum based on the National Curriculum in England. Apart from their daily Spanish class, they learned everything in English. We had no teaching assistants but we did have one SEN teacher who did the most brilliant job. At times the going was difficult but every child tried their best, teachers worked their hardest and when the SAT's in English and Maths were taken we never doubted that the results would be similar to if not better than those from England's primaries. And every year the children proved themselves by doing just that.
How could that be?
It's quite simple really. There isn't a magic bullet, no secret teaching method nor learning style is used. What that school and many other international schools do is to leave out all the nonsense from government and trust their teachers to do the job they know best. Teachers are left to teach, to use the curriculum in the way they see fit, to change and adapt to the learners in their class. The trust between teacher, child, SMT and parents keeps the school at its best. Teachers don't have to face mountains of paperwork, the goal posts never change half way through the year, there are no 'Ofsted' style inspections but there are inspections that promote teaching and learning, there are no ridiculous SMT demands nor league tables (schools work together), work scrutinies are used to pick out great ideas not to find negative issues, there's no mad fixation on formal assessment, no APP nor AfL as created by government but definitely a system in place that works for the children in the school, there's no marking in green and pink only marking and it doesn't involve detailed responses nor next steps. The list could go on but I'm sure you get the point.
Schools in England need to leave out the nonsense that doesn't benefit the learners, then we'll see our education system start to improve.