Chris Pearce has an MA in maths and over 30 years' teaching experience at secondary level through KS3 to KS5. Now a full-time author, education advisor and examiner, he has written many bestselling KS3 and KS4 materials for Collins. Helen Ball is co-author of the new Collins Core Maths resources. She is an ex-IT project manager who switched to maths teaching, rising to Head of Mathematics and teaching from KS3 through to KS5. She is an IGCSE and A-level examiner. Michael Kent has 20 years' experience teaching Pure Maths, Mechanics and Statistics for AS and A Level Mathematics and Further Mathematics, twelve of them also leading a successful department. He co-authored the most recent editions of Collins' GCSE Maths Student Books. Kath Hipkiss has taught Mathematics for 14 years, being an Advanced Skills Teacher, Head of Department and now a Lead Practitioner teaching KS3 through to KS5. She wrote the latest Collins' GCSE Maths Foundation Practice book. She has been an Edexcel examiner for 8 years.