Inspiration for this project are the climate strikes world-wide, in which students strike for climate justice. The children participating in these strikes indicate that they do not feel heard. While striking is relevant to communicate their opinions, change can also be initiated by changing the perspective of for example parents/guardians. This led to the initial design brief to ‘help minors of the age 12 to 14 to take agency in developing strategies to decrease environmental impact in their home environment’. The first phase of the project was the research phase. Agency in sustainability consists of a combination of the readiness to change behaviour and the feeling of self-efficacy one has. One does not only have to believe in their own ability to become more sustainable, but also must believe that those efforts make a difference. The research showed that an additional motivation to be more sustainable (saving money, being healthier) was the reason people stayed motivated in their efforts to be more sustainable. This study provided an overview of factors that influence the self-efficacy and the readiness to change their behaviour, which together determine whether there is the possibility to take agency over a situation. A lack of intrinsic motivation and existing beliefs regarding sustainable habits or the value of current habits limit the readiness to change behaviour. A lack of information or highly complex information, a lack of constructive reflection, and unclear intention setting limit a feeling of self-efficacy. The following design goal was formulated: I want children of the age 12 to 14 to feel an appreciation for food when deciding what to eat together with their parents. My goal is not only to help them eat more sustainably, but also to help the family reflect on the value of current food habits in open. I determined the following desired characteristics: surprising, appreciative, connecting and in control. Food for Thought helps families to pick meals based on what their limitations or values are on certain days of the week instead of what type of meals they want to eat. This responds to the limitation of not making concrete plans to realize intentions. It is a card set with a mobile application. The cards have on one side different categories of values, ('quick', or 'a treat'), On the back of the cards there are recipes that fit with the value they chose. Giving the family a sustainable meal idea ensures they have all the information necessary to prepare a sustainable meal, thus making it easier for them to fulfil their sustainability goal. In this way the design bridges between intention setting and self-reactiveness and helps them discuss sustainability with the family. This method of bridging between intention setting and self-reactiveness was useful to let the families look at their food habits differently and proved to be both educative and easy to implement. Using values to provide users with a fitting approach to behavioural change could be used in other situations where a change of behaviour is fitting.