Archaeological monitoring was carried out in 2017 and early 2018 during groundworks for the construction of a new teaching block, associated car parking and access routes at the school, as well as a multi-use games area (Colchester Borough Council planning application 161668).<1><2> The first phase of monitoring, between January and March 2017, focussed on the excavation of service trenches, attenuation tanks and ground reduction along a new access road route. This work did not identify any archaeological remains relating to either the Lexden Dyke or Heath Farm Dyke, or encountered any Late Iron features possibly associated with them. All encountered remains were either boundary ditches of certain or probable post-medieval/modern date, or else were undated features of uncertain type. One ditch, a field boundary shown on historic OS survey mapping up until the 1950s, was a further part of that recorded during the evaluation. The site had been disturbed to some extent by the insertion of a substantial service trench in the modern period, perhaps at the time of the school’s construction.<1> Monitoring was carried out between November 2017 and January 2018 during the groundworks for the MUGA. The monitored works for the MUGA included topsoil stripping, the excavation of drain runs and catch pits and the excavation of construction pits for floodlight bases. No archaeological remains were found relating to either the Lexden Dyke or Heath Farm Dyke, or any Late Iron features possibly associated with them. Two undated cut features ([029] and [031]) both in Catch Pit 3 at the western corner of the MUGA), one of which was a small ditch or gully [031], were found.<2> The archaeological monitoring followed a geophysical survey and also trial-trenched evaluation in 2016.<3><4>