First year undergraduates, on a systems physiology unit, write a summative timed essay. One aim of this is to train students in scientific writing as many will have had limited prior experience. A marking grid, developed at Bristol, is used to assess writing skills for which 50% of the marks are allocated and 50% is for scientific content. Prior to the assessment students write two formative essays receiving feedback from staff. Following the first practice essay some students anxiously requested more essay writing practice and feedback. In response an optional workshop was run which aimed to: give all students an opportunity to practice essay writing; improve students’ confidence in planning and writing essays; provide good quality feedback, with minimum staff input. All 186 students taking the unit were invited to an essay writing workshop. Interested students were given a title prior to the workshop and asked to bring an essay and an attempt at a scientific content mark scheme, 20 attended. In the session groups students were allocated a section of a skeleton mark scheme to discuss. Their suggestions were fed back to the whole group and a master mark scheme composed. Students were given 15 minutes to marked an essay and write feedback comments. They were then encouraged to give verbal feedback to each other. Students completed pre and post session questionnaires which included a self-assessment of confidence in planning and writing essays on a 1-5 scale, 5 being high. Permission was gained from all students to collect their marks for their other essays. Attendees marks for two practice essays (essay 1 pre & essay 2 post workshop) and the summative essay were compared (mean ±SEM, unpaired T test) with those of students who did not attend. Students reported attending the workshop to improve essay writing skills (74%) and to improve scientific essay content (16%). 89% of students agreed that the session had fulfilled their goals. The questionnaire showed a reported increase in attendees’ confidence for essay planning from 2.8 ±0.2 to 3.5 ±0.2 and for writing timed essays from 2.0 ±0.2 to 2.7 ±0.2. The mean mark for essay 1 was similar for both attendees (72.8% ±2.8) and the rest of the cohort (73.8% ±0.9). Attendees did better in the essay 2 than non-attendees (mean mark 65.0% ±2.3 vs 60.3% ±1.1) and in the final summative essay (mean 57.3% ±1.9 vs 53.3% ±1.1). However this was not statistically significant: for essay 1, p=0.7, for essay 2 and summative essay, p=0.08. This workshop provided students with an extra opportunity to practice essay writing, and improved students’ confidence in this type of assessment. Those students who attended the session achieved a higher mean mark in the summative exam. The peer review aspect of the workshop also gave students the opportunity to experience other students’ writing styles and set a framework for them to follow in their independent study.