<p>The National Strategy for Primary Schools in England (2006) advocates synthetic phonics as a means forteaching children to read. No studies exist to date comparing the effectiveness of different commercially available synthetic phonics methods. This case study compared two schools at which Jolly Phonics (JP) was taught with one school at which THRASS (Teaching Handwriting, Reading and Spelling Skills) was taught at Receptionlevel (4 to 5 years) over a one-year period. Reading ability for words and non-words as well as short-term memoryability for words and phonemes improved in all schools. However, reading ability improved more in one JP schoolcompared to the THRASS school, with no differences between the other JP school and the THRASS school. Thispaper considers how particular variables may mask instruction method effects, and advocates taking suchfactors into account for a more comprehensive future evaluation of synthetic phonics methods.</p>