We evaluate whether the placement of Teach First's inexperienced new teachers into secondary schools with recruitment difficulties in disadvantaged areas in England has raised or lowered pupil attainment at the age of 16. Our matched difference-in-difference panel estimation approach compares the experiences of 168 schools participating early on in the scheme to those in the same region who will go on to participate in later years. We find the programme has not been damaging to these schools who joined and most likely produced school-wide gains in GCSE results of around one grade in one of the pupils' best eight subjects. Similarly, we estimate departmental gains of over 5% of a subject grade resulting from placing a Teach First participant in a teaching team of six teachers. The estimation approach cannot assert whether these gains arise solely through the greater teaching quality of Teach First participants compared to those they displace, or whether spillovers raise standards across the department or somehow change the ethos within the school.