You don't have to postpone your evaluation until the end of your project. Questioning your participants before or during the course of the study is also very useful; it enables you to map out the expectations of your participants at a time when adjustment of the project is still possible. Even if you want to measure the impact of participation afterwards, it is good to have a baseline measurement from the start of the project to be able to compare. A good example in which the impact on the participants was carefully measured is the study (in Dutch) that HIVA (KU Leuven) conducted at CuriezeNeuzen.
- At the start of your project, determine the indicators according to which you want to evaluate your project (qualitative and quantitative).
- Do interim evaluations during the project so that you can make adjustments if necessary.
- Prepare a final evaluation, list 'good practices' and 'lessons learned' and post them somewhere online so that others can learn from it.
Tina Phillips, Norman Porticella, Mark Constas, Rick Bonney, A Framework for Articulating and Measuring Individual Learning Outcomes from Participation in Citizen Science (in: Citizen Science: Theory and Practice, Augustus 2018)
Tina Philips, Marion Ferguson e.a., User's Guide for Evaluating Learning Outcomes From Citizen Science (Cornell Lab of Ornithology, 2014).
Luigi Ceccaroni, Claire Williams e.a., MICS project (Measuring Impact of Citizen Science)