Judged excellent by ISI Thames Christian School is an Independent Secondary School for Girls and Boys aged 11-18 close to Clapham Junction Station in Battersea, London. Pupils benefit from the school's strong Christian ethos and pastoral care along with excellence in academic and creative subjects., Judged excellent by ISI Thames Christian School is an Independent Secondary School for Girls and Boys aged 11-18 close to Clapham Junction Station in Battersea, London. Pupils benefit from the school's strong Christian ethos and pastoral care along with excellence in academic and creative subjects.