The onset of war in September 1939 had the immediate effect of totally disrupting the life of the school. Walthamstow was an evacuable area under the Government's regulations, though at first Chingford was not. The school was convened early on Monday 28 August, when war was judged imminent. There followed a week spent waiting, which was occupied largely in games, the holidays officially continuing.
Evacuation took place on 2 September, the school being accommodated in a special L.M.S. train from Black Horse Road Station to Ampthill in Bedfordshire. Ampthill is an ancient market town, but a very small one. The boys were billeted both in the town itself and in the surrounding villages of Marston Moretaine, Maulden, and Lidlington. Groups of boys, ranging from 45 to 100, were billeted in each place, and four or five masters accompanied each contingent. Attached to the party were the younger brothers (and sisters) of the Monoux boys. At Lidlington, the villagers were expecting a party of primary schoolgirls, and at Maulden (to quote from a contemporary account) "one master found himself doomed to share a solitary single bed with four others".
Lessons, from 16 September, took place in various church halls in Ampthill, in the Wesleyan Chapel and the Union Chapel. Lessons were somewhat attenuated in scope at first, since there were no textbooks, ink or blackboards. Evening, weekend, and in some cases, afternoon, activities had to be organised, and these took the form of walks, filling sandbags, helping local farmers, A.R.P., first-aid, and games, including one euphemistically known as "progressive table tennis".
On 17 November, the school was moved to Colchester. This time the evacuation was by bus. The idea was probably to re-establish the school as a single unit, in one place. No.12 Lexden Road became the "Monoux House" - a place for storage of books, a staff and prefects' room, as well as a room variously used for classes and recreation. From Colchester, 48 miles from Walthamstow, many of the boys were able to cycle or take the train home for weekends and at holidays. It must not be forgotten also that many parents had recalled their sons, largely because of the lack of air raids in the early months of the war. In Colchester, the Monoux School worked in the Royal Grammar School, in various of the town's schools and in the Technical College. Success in examinations was maintained after a year of evacuation, though, of course in lower numbers. In Colchester the boys found themselves in relatively familiar surroundings and life seems to have presented a less rustic and makeshift appearance than it did in Bedfordshire.
However, the School moved yet again, this time by train from Colchester on 2 June 1940, and arrived eventually in Bromyard, in Herefordshire. The move was occasioned, one suspects, by the fears of invasion, for a decision had been taken by the Government during the late Spring to make Colchester itself an evacuable area, and the date set for this was 1 July 1940. In Colchester, the School was billeted almost on the east coast. In Bromyard, it was in the rural Marches of Wales.
The Bromyard interlude lasted only a fortnight. Thereafter the bulk of the school travelled by coach to Leominster, also in Herefordshire, but about 36 first formers were accommodated at Lucton School, about five miles from the town. Leominster proved the longest stay, and when evacuation is remembered by former Monovians, it is to Leominster that their thoughts principally return. In early 1942, there were twelve masters in Leominster including the one at Lucton. The number of evacuees was variable, but it reached a maximum of just under 200. Lessons were held largely in the town's small Grammar School, three full days a week, and half days on Saturdays and two other days. Holidays usually prompted a mass return to Walthamstow, despite official disapproval. A new Headmaster, J F Elam, took office after Christmas 1941 to replace P. D. Goodall, who left suddenly. The reasons for his departure have never satisfactorily been made public. Mr. Emery, Second Master, took charge in the intervening period. The School seems to have acclimatised quickly to Leominster life. There were two distinct views of evacuation, those of the evacuee and those of the host. Monoux memories of Leominster are varied. There were undoubtedly difficulties; in teaching, in being away from parents and homes, and in billeting. From the point of view of the townspeople, the infusion of 200 boys meant inconvenience and a disruption to the normal run of things. The organisation, for instance, of evening activities was of mutual benefit, releasing the hosts to something like their former privacy, and the boys to the companionship of their friends. In the end, the Monoux Social Club functioned six nights a week. The Leominster view of the school is not recorded.