YELLIS, the YE ar 11 I nformation S ystem,  provides innovative tests widely used in the UK and elsewhere, forming a baseline for value added measures in secondary schools. Currently taken by around 200,000 student in over 1,200 secondary schools, the Yellis baseline tests are available for years 10 and 11 (i.e. for students aged 14-16) with value added measures to GCSE.