Básico 1 and Básico 2 students will greatly benefit from this website which prepares ESO students in Spain for the big day on 10 May 2012, although learners of all levels can give the site a try and will really enjoy it.
There are four different levels of difficulty, and three modes within each level (training, normal, fast). Each test consists of 21 questions which include grammar, vocabulary and pronunciation.
H/T to Ani Anievas.
