Leadership team

Headteacher and Deputy DSL
Mrs Helen Cullen

BSc (Hons)
Sports and Exercise Science with Human Biology

Mrs Cullen was educated at Leweston School in Sherborne before studying a degree in Sports and Exercise Science with Human Biology. She completed her PGCE at St Luke’s, Exeter University. With a teaching career based in the South West, Mrs Cullen has worked in schools in both Devon and Somerset, starting her career as a PE teacher before quickly progressing to middle leadership positions, including Head of Year and Head of PE.

Mrs Cullen joined Sexey’s in September 2018 after being Vice Principal at Preston School in Yeovil for 10 years. During this time she was the whole school lead for pastoral matters including safeguarding, students’ wellbeing and support, student achievement and vulnerable students. Having been a SENDCo for eight years, Mrs Cullen is passionate about inclusion and ensuring education is accessible for all students and that no student is disadvantaged by opportunity or resource. She is Designated Safeguarding Lead at Sexey’s.

Mrs Cullen is delighted to be leading the school and staff at Sexey’s and will be further developing the strong reputation that Sexey’s has for being a highly successful State Boarding school, with strong GCSE and A level results.



Deputy Headteacher - Curriculum, Data and Standards
Mr Ross Dalzell

BSc (Hons)

Mr Dalzell joined Sexey’s School in April 2019, having worked at King Arthur’s Community School as Assistant Headteacher – Curriculum and Assessment and Head of Mathematics since 2014. While there, he led on curriculum development, timetable design, examinations and data, and implemented strategies to improve students’ progress. He brings this knowledge with him to Sexey’s, along with a passion for tailoring solutions so that each student has a unique learning and development experience.

A keen traveller and sportsman, Mr Dalzell has participated in many running events, triathlons, multi-obstacle races and the round the Isle of Wight yacht race. This is alongside building his teaching career in schools in Portsmouth, Somerset and Dorset since completing his PGCE in Mathematics at Cambridge University in 1999. He also enjoys spending family time with his wife and young daughters.


Assistant Head - Teaching and Learning
Mr Adam Thomas

BSc (Hons)
Sports and Exercise Sciences with Psychology

Mr Thomas was educated in West Sussex before studying a degree in Sport and Exercise Sciences with Psychology at Cheltenham, Gloucestershire.

Prior to completing his PGCE at the University of Brighton he worked in sales and marketing for some global brands; an area that still remains of great interest to him.

Mr Thomas started his teaching career as a PE teacher in West Sussex before progressing to the role of Head of Department, a position he has also held in schools in B&NES and Wiltshire, all of which have broadened his experiences of differing educational establishments. Alongside his teaching and middle leadership responsibilities, Mr Thomas has also been responsible for school provision for ITT, NQT and Teacher coaching.

Mr Thomas is passionate about teaching and learning, the student experience and teacher development, which led him to build on his previous roles in education and become Programme Leader for Teacher Training at Weston College, one of the top rated FE colleges in the country. Working within the Quality of Teaching and Learning department he was responsible for the delivery of teaching qualifications, and focused on wider staff training and CPD.

Sport has always played a big part in Mr Thomas’ life, and this passion has been passed on to his own children, who are all keen sportspeople.

Mr Thomas is excited about continuing to develop the area of Teaching and Learning at Sexey’s, as well as leading the Careers programme.


Assistant Head - Pastoral and Safeguarding Officer
Mr Philip Clackson

BSc (Hons)

Mr Clackson joined Sexey’s in 2002 as Head of Mathematics. He also served as Housemaster of Walwin House from 2003-2008 and was a Staff Governor from 2008 – 16.

Mr Clackson became Assistant Head – Pastoral in 2016 and sits on the School’s Safeguarding Team. He is also father to four children who have all attended Sexey’s, making him well placed to understand the challenges and expectations of both secondary school students and their parents!


Director of Sixth Form
Mr John Moise

Med, BSc (Hons)
Sport Science

Mr Moise was educated at Sturminster Newton High School, and then The Gryphon Sixth for A-Levels, before studying a degree in Sport Science at Swansea University.  He completed his PGCE and Masters degrees at St Luke’s, Exeter University.  Mr Moise has taught across both Dorset and Somerset to date, starting his career as a PE teacher in Weymouth, before moving to become Head of Year at Preston School in Yeovil.

Mr Moise spent eight years at Preston School in Yeovil, where he was fortunate enough to be able to teach PE, Geography, ICT, French, and Foundation Learning.  During this time he was able to take on a part time role as the Acting SENCo, while his final three years involved guiding a year group from Year 9 through until their final exams in Year 11.

With a passion for PE, comes a love of everything outdoors and Mr Moise has been involved in many Duke of Edinburgh expeditions, school ski trips, and sporting trips.  This all stems from his initial employment endeavours as a Ski Instructor in North America and an Outdoor Activity Instructor in the New Forest.

Mr Moise is excited to be able to draw on all of his experiences to date to help further build and raise the profile of the Sexey’s Sixth Form within Somerset.