In May 1940, shortly after the closure of the ghetto, hundreds of young people settled in houses in Marysin (see), organising their lives according to kibbutz models. Jakub Poznański (see), head of the Agricultural Department (see), which was responsible for Marysin at the time, witnessed the birth of the Hachshara movement and was partly involved in its organisation. Poznański divided the young people into three groups: Zionist, marked with letters (letter groups), non-Zionist, marked with Roman numerals, and secondary school, marked with Arabic numerals. The lack of traces in the preserved archival documentation gives grounds to believe that the secondary school groups operated for a very short time, and the young people dispersed among others or returned to their families.

The Zionist groups were the most numerous and active. They formed the Executive Committee of Literary Groups (Mazkirot szel Waad Ha-Kibucim), also known in Polish as the Secretariat of Literary Groups, with its headquarters at 46a Przemysłowa Street. According to Izrael Tabaksblat (see), kibbutzim of the following parties operated: General Zionists: 4 kibbutzim, 180 members, Poale Zion-Right (3, 120), Hitachdut Gordonia (2, 130), Ha-Shomer Ha-Cair (1, 40), Revisionists (6, 300), Judenstaatspartei (1, 40), Mizrachi (3, 100). There were initially 28 letter groups. The size of the groups (kwuc) ranged from 24 to 28, although there were groups consisting of 95 people. The maximum number of members was around 1,000. The size of the groups changed as people left Marysin and moved within the houses.

Non-Zionist number groups formed the Main Board of Number Groups, based at 10 Roberta Street. Roberta 10. According to data from August 1940, there were 27 Roman digital groups with 344 members, including 277 boys and 67 girls aged 18 to 22, although there were also younger people, even as young as 15.

Each group had a leader who was responsible for order and was required to attend meetings convened by the Main Board of Digital Groups, as well as a guardian (patron). Among the guardians were, among others, Maurycy Siemiatycki (see above), Bronisław Dancygier (see above), lawyer Samuel Bronowski (see above) and Pinkus Gerszowski (see above). The individual digital groups were made up of people who shared political or religious beliefs. For example, group IX (based at 28/32 Zagajnikowa Street) was associated with the Bund. It consisted of 15 boys and 7 girls. The group was led by Binem Wiener (see above), a member of the Bund youth organisations Cukunft and Skif. Group XXVII was a religious, Hasidic group, hence the letter ‘Ch’ appearing in some documents. It was located in a house at 129 Okopowa Street and had 25 boys. Its patron was Rabbi Szmul Dawid Łaski (see above). Separate groups were formed by the graduates of the Industrial School (No. IX, 28 Zagajnikowa Street), another group of Hasidim – No. XVII, based at 19 Karola Miarki Street, Kacenelson's school (No. XIX, 7 Niemojewskiego Street), the Bar Kochba association (No. XX, 7 Brudzińskiego Street), Ha-Ko Karola Miarki Street 19, Kacenelson's school (No. XIX, Niemojewskiego Street 19), the Bar Kochba association (No. XX, Brudzińskiego Street 7), Ha-Koach (No. XXI, Zagajnikowa Street 9).

Symbols for both groups were designed, and seals and office paper were produced. The secretariats were responsible for matters such as funerals of Hachshara members, clarifying registration issues, granting financial assistance, issuing referrals to hospitals, admission to secondary schools, as well as economic issues, including ordering products from the Economic Department and the removal of faeces.

A militia (Milicja Marysin II, abbreviated MMII) was formed from among the members to maintain order in the Hachsharas. In August 1940, 119 members of the Hachsharas were assigned to the militia.

The most active period of the hahshara was in the summer of 1940. The young people quartered in Marysin learned to work on the land and were responsible for gardens and orchards. They were also sent to work on paving roads and squares. Female members of the Hachshara were given jobs in kitchens and offices or as carers at camps organised in Marysin (see below). The Hachshara also received requests for workers for various jobs in the ghetto, e.g. in the hospital on Drewnowska Street or in orphanages.

On Sunday, 27 July 1940, a review of all groups took place in the presence of Rumkowski (see). This event was widely documented in photographs. The head of the Jewish Council stood on a specially prepared podium and received the parade of young people. According to Jakub Poznański, about 3,000 boys and girls marched past the President, shouting ‘Long live the prince’ in Hebrew.

Free time was devoted to education – lectures and talks on the history of the Jews, Palestine and economics were organised, as well as Hebrew lessons for those interested and gymnastics classes. On the initiative of literary groups, a rich programme was prepared to commemorate Włodzimierz Żabotyński, a Zionist activist and founder of the New Zionist Organisation, who died in America in August 1940. The celebrations organised in honour of Theodor Herzl and Nachman Bialik, which were attended by several thousand people, also resonated widely.

The crisis of Hahshara activity began in the autumn of 1940. There was a rift between the idea of agricultural training and the young people's desire for self-education and work for the benefit of society, and the reality. In late autumn, there was no more farm work, and there were problems with food and forced labour. Instead of the work on farms and in gardens planned by young people, there was a demand for tailors and shoemakers in connection with the planned launch of ministries in Maryn. The non-Zionist groups were the first to disintegrate. From November 1940, many members left their kwuces. New members were accepted in their place, but this was not on a large scale. People who sympathised with the movement came to Marysin, even though they were no longer officially registered as members of the movement. For example, Lolek Lubiński (see above) visited his friends in Marysin as late as January 1941. Ultimately, the Hachshara was dissolved in March 1941.

The Hachshara movement played a very important role in the lives of young people and influenced subsequent phases of life in the ghetto. Living in Marysin, finding themselves among people of similar age and views, and having the opportunity to independently engage in the practical implementation of the principles of kibbutz life, which had been discussed theoretically until the war, allowed these young people to avoid the problems that befell the rest of the ghetto population at that time. They were not directly affected by the spectre of hunger, as they had farmland and the right to use the crops. They had flats, which they cleaned and furnished themselves. The group's management took care of basic needs, such as hairdressing services, buying toothpaste, health checks and referring people to doctors. Cultural activities and education certainly became the glue that held the groups together. The ideal world of the kibbutz pushed aside for a few months the problems that their families faced in the ‘city’, as the ghetto was called in contrast to Marysin. This movement did not die out completely, although it ceased to be mass in nature and was no longer based on the hachshar structure (see Informal youth groups).