Understanding scientific concepts is a crucial factor in motivating dabblers at the start of co-created citizen science projects. This article describes PACMAC, a card-based cooperative card game aimed at introducing dabblers to hypothesis and falsifiability concepts through the visualization of a social perception map. The game was evaluated in five neighborhoods from El Salvador. The results showed that PACMAP is approachable for participants of different demographics to develop an understanding of the concepts of hypotheses and falsifiability.

Over 500 delegates took part in the third international ECSA conference in September 2020. Across 30 sessions, as well as keynote talks, e-poster presentations and more informal settings, they discussed and debated a diverse range of subjects related to citizen science. This special edition of ‘JCOM’ brings together some of the central themes that were under the spotlight at ECSA 2020. Since ECSA 2020 has been one of the first examples of a conference that moved completely online, and it has been considered a big success, we also include the Conference Report, as supplementary material with this editorial.

Positioning citizen science within the broader historical public engagement framework demonstrates how it has the potential to effectively tackle research and innovation issues. Citizen science approaches have their own challenges, which need to be considered in order to achieve this aim and contribute to wider and deeper public engagement. However, programme evaluations, which discuss lessons learned in engaging the public and other stakeholders with science are rare. To address this gap, we present the H2020-funded DITOs project and discuss the use of logic models in citizen science. We share the project’s assumptions, design considerations for deeper engagement and its impact pathways demonstrating how logic models can be utilised in citizen science to monitor programme effectiveness and for their successful implementation. We hope that this work will inspire citizen science practitioners to use similar tools and by doing so, share their experiences and potential barriers. This knowledge is essential for improving the way citizen science is currently practiced and its impacts to both science and society.

Acknowledging the consolidation of citizen science, this paper aims to foster a collective debate on two visible gaps of the field. First, how to overcome the limited participation of social sciences and humanities in the broader field of citizen science, still dominated by natural sciences. Second, how to develop a citizen social science that allows for an active participation of citizens and for a critical engagement with contemporary societies. The authors coordinate a state-sponsored program of scientific dissemination within a Portuguese research institution and this paper intends to lay the groundwork for a future project of Citizen Social Science based on a new concept of “engaged citizen social science”.

Co-created citizen science offers practical tools for implementing science communication theories by increasing public participation in scientific research, empowering communities and advancing situated scientific knowledge. However, delivering such an approach presents a number of key challenges around funding, fostering working partnerships between scientists and citizens and ensuring all stakeholders receive sufficient benefits from the process. In this essay we draw from science communication and citizen science literature to describe these challenges and discuss the opportunities that will enable co-created practices to prosper.

A Science Shop acts as a mission-oriented intermediary unit between the scientific sphere and civil society organizations. It seeks to facilitate citizen-driven open science projects that respond to the needs of civil society organizations and which, typically, include students in the work process. We performed a thematic analysis of a systematically selected literature on Science Shops to understand how the scientific literature reflects the historical evolution of Science Shops in different settings and what factors the literature associates with the rise and fall of the Science Shop. We used the PRISMA methodology to search for scientific papers in indexed journals in eight databases published in English, French and Spanish, and employed the thematic theory approach to extract and systematize our results. Twenty-six scientific articles met the inclusion criteria. We identified three meta-categories and ten sub-topics which can serve as key pointers to guide the set-up and future work of Science Shops. Our results identify a major paradox: Science Shops incorporate public values in their scientific agendas but have difficulties sustaining themselves institutionally as they do not fit the current dominant research paradigm. Science shops represent a persuasive complementary approach to the way science is defined, executed and produced today.

A new regime of science production is emerging from the involvement of non-scientists. The present study aims to improve understanding of this phenomenon with an analysis of 16 interviews with Spanish coordinators of participatory science practices. The results indicate a majority of strategic and captive publics and point to communication as a key tool for the development of successful practices. Five key elements of the degree of integration required to develop a citizen participation in science practice were analysed: derived outputs, level of participant contribution, participation assessment, practice replicability, and participant and facilitator training. Proposals for strategies to remove barriers to citizen participation are the study's principal contribution.

BioBlitzes, typically one-day citizen science (CS) events, provide opportunities for the public to participate in data collection for research and conservation, potentially promoting deeper engagement with science. We observed 81 youth at 15 BioBlitzes in the U.S. and U.K., identifying five steps participants use to create a biological record (Exploring, Observing, Identifying, Documenting and Recording). We found 67 youth engaged in at least one of the steps, but seldom in all, with rare participation in Recording which is crucial for contributing data to CS. These findings suggest BioBlitzes should reduce barriers to Recording for youth to increase engagement with science.

Citizen science is a transdisciplinary approach that responds to the current science policy agenda: in terms of supporting open science, and by using a range of science communication instruments. In particular, it opens up scientific research processes by involving citizens at different phases; this also creates a range of opportunities for science communication to happen This article explores methodological and practical characteristics of citizen science as a form of science communication by examining three case studies that took different approaches to citizens' participation in science. Through these, it becomes clear that communication in citizen science is ‘÷always’ science communication and an essential part of “doing science”.

Digital citizen science projects differ greatly in their goals and design. Tensions arise when coordinators' design choices and conceptions of citizen science conflict with users' motivations and expectations. In this paper, we use a combination of qualitative methods to gain new insights into the ways citizen science is understood and implemented digitally. This includes a study into the affordances of two citizen science portals for bird observations, and qualitative interviews with users and coordinators of the portals. This reveals tensions related to data sharing, community hierarchies, and communicated expectations. Awareness of these tensions can benefit the future design of online citizen science projects.