"organised into groups" is correct and usable in written English.
You can use it to describe how different items or people are divided and categorised. For example, "The attendees were organised into groups and assigned to different tasks."
All that was required was for people to be organised into groups in the first place.
Farmers were organised into groups and given training in new farming techniques.
It's the same story for the 2,000 farmers organised into groups of 30 in farmer field schools as part of a project involving World Vision.
The inventor formulated the periodic law – which states that elements can be arranged by their mass and be organised into groups that share similar chemical and physical properties.
Expeditions are organised into groups of five to 12 and guided by an experienced leader, with three nights out of 14 spent camping, the others in mountain refuges, hostels and a hotel.
The think-tank was organised into groups examining five key areas: temperature and extreme weather events, infectious disease, food and water supplies, livelihood and disadvantage, and security, social instability and conflict.
The community has also been organised into farmers' groups, a store has been built for them and they are being organised to market their produce collectively.
"Some of the prisoners have organised into armed groups and resist their indefinite detention by firing rockets over the prison wall.
These habitats are therefore a key indicator of biodiversity and although organised into nine groups, there is no way to identify them other than by gaining familiarity with the list.
The same thing happens in the neighbourhoods, overwhelmed by the insecurity that reigns over the city, where people are organised into watch groups to defend themselves against robbers or to cart the rubbish accumulated in the street to the corner to burn it.
Data was then organised into 2 groups (pre and post guideline) and analysed using SPSS.
