New figures have revealed that the influx of migrants from Eastern Europe has helped English become the second language at one in nine schools.
According to the campaigners, the figures highlight the strain that the schools are going through to educate the 1.1 million kids who speak in another tongue, Daily Star reported.
Anastasia De Waal, from think-tank Civitas, said that the problem of resources risked damaging youngsters' education.
She said that in too many cases their schools are simply not set up to accommodate very high proportions of kids who start school without fluent English.
De Waal said that those who lose out most in this scenario are these very pupils, as they don't receive adequate opportunities to develop their English language skills, and are therefore at risk of going through the education at a significant disadvantage.