Do you leave the lights on when you are no longer in the room? Modern lamps consume little electricity, but it is still worth not leaving them on unnecessarily, for example when we are not in the room for a long time.

Do you have a large (0), medium (1), small (2) or no (3) room of your own? The space we need to live in means the area that is sealed, the building materials that are required and the space that needs to be heated – and all this against the backdrop of social justice. When more people live in a household, they share rooms such as the kitchen, living room or bathroom. In fact, the per capita area is increasing continuously because more older people are living alone and longer in large houses and because there are more single households. Not everyone can renovate or move out, but those who take these steps can be proud of reducing their living space. Very few children and young people can now decide how big their rooms are. But those who have a small room or share it with siblings can be proud of it and collect the points.

Intelligent ventilation means not too late and not too long. It is too late when we become tired from stale air, get headaches and the humidity becomes too high. It is too long when the air has already been exchanged and is cool, but we continue to ventilate and then the materials (walls, furniture) also cool down. Ultimately, heat means that things or air vibrate. When the air has been replaced but the objects and walls are still vibrating, the fresh air quickly warms up. If the walls also become cold, mould can form on them and we need expensive heating energy to get everything vibrating again. CO2 measuring devices help to ventilate at the right time and not for too long. However, these should not be useless gadgets, but perhaps used to practise one after the other in the rooms and also lent out. A nice game is to compete to see how good people's sense of timing is when it comes to ventilating at the right time and not for too long.

Organic is extremely important for biodiversity. We have the greatest species extinction since the extinction of the dinosaurs and the consequences are greater than those of climate change. Pesticides and mineral fertilizers endanger our future. In addition, soils from organic farming usually store more carbon and thus help against the climate catastrophe. The counter-argument is often that the yields in organic farming are lower than in industrial agriculture and therefore more forests have to be cut down. This is true, for example, with cereals that are not unrestrictedly healthy. But if we eat less meat, waste less food and eat more healthy legumes, we have plenty of additional space available and can feed the entire world organically and even plant a little more forest. Organic is more expensive. But on the one hand, many costs can be saved by less meat and on the other hand, it can be bought and cooked intelligently …. of course, it is also to be questioned whether there must be such a low livelihood at all - environmental policy is also social policy.

Fortunately, tap water has long been a trend. Schools have drinking fountains and pupils bring their own water bottles, and managers also bring their water bottles to workshops. Many children are not even accustomed to unhealthy sugary drinks. Tap water is more strictly controlled than bottled drinks and saves a lot of energy and packaging. Even in motorhomes or boats, or in places where the water smells of chlorine, we can save a lot of money, energy and packaging by using good filters that are changed regularly.

Do you sometimes throw food away? Or do your parents throw away food that you didn't eat in time? Food is wasted from the field to the factory and transport routes to the point where we, restaurants and supermarkets throw it away. Ultimately, this means that more land is needed for cultivation, which leads to deforestation and endangers biodiversity with pesticides and fertilisers. We can shop more selectively, avoid throwing away goods just because of their best-before date, save food in the household (e.g. freezing bananas or making long-life spreads and soups from leftover vegetables), saving specifically rescued food (e.g. goods that are too small or shriveled) and, in many places, donating leftover food, e.g. to food banks.

Local public transport and also long-distance transport by train and bus (in the case of bus, the road infrastructure is still required) means considerably less energy and resource requirements than individual transport with cars or motorcycles. Long-distance buses only perform so well because they are limited to well-used routes, while the train also runs at unfavorable times and has to connect remote places, which then leads to less than half-full trains.

Consistently separating waste, including green waste, glass and paper, is not as self-evident as can be assumed. Many make little effort here and don't really know what belongs in which bin. But also special waste, such as batteries, incandescent lamps, electrical appliances, etc. must be disposed of properly.

Canned drinks are truly awful! After buying unpackaged goods and drinking tap water, the best thing we can do is to buy our food in reusable containers. (Incidentally, there are also reusable shipping boxes for office supplies, as well as some regional delivery services). It is also important to ask whether the containers are transported empty throughout Germany, or whether North German beer is poured into empty Bavarian beer bottles and vice versa. The next question is how much energy it costs to clean the containers. Composite packaging or easily recyclable cans are the better alternative in some studies. In such studies, it is important to look closely at what is being compared. Ultimately, the aim is to close regional cycles. The next question is whether the containers should be made of glass or plastic – glass is recycled more often, while plastic is lighter and requires less energy to transport.

We are used to buying safe and durable food conveniently at the supermarket. It is packaged, and since we separate our rubbish, we hardly have a problem with it. In reality, however, only a certain amount of waste is recycled – much of it is incinerated or still exported. But we can make many foods ourselves and buy the ingredients unpackaged or with minimal packaging. It takes a bit of effort, but it saves money and a lot of packaging. We can make bread, spreads, sauces, juices, jam, etc. ourselves – everything that would otherwise be bought packaged. The fruit can come from the garden or orchards – this promotes the demand for insect-friendly orchards, and if we do all this together with others, or at least exchange the yield with each other, we strengthen the community.