The Primary Games Arena has some great little games for children to learn specific things from the primary curriculum, be it nouns, multiplication, spelling or coding. It is sorted into age groups and subjects.  I can see it working well with some of the ESOL students who could try their hands at the quick quiz section as an  extension to classroom activities or interactive games where they can identify nouns, spellings or find the missing word. (There are some ads so the site needs some supervision whilst the children are using it.)