Micro-tasking (e.g., crowdsourcing) has the potential to help “long-tail” senior workers utilize their knowledge and experience to contribute to their communities. However, their limited ICT skills and their concerns about new technologies can prevent them from participating in emerging work scenarios. We have devised a question-answer card interface to allow the elderly to participate in micro-tasks with minimal ICT skills and learning efforts. Our survey identified a need for skill-based task recommendations, so we also added a probabilistic skill assessment model based on the results of the micro-tasks. We also discuss some scenarios to exploit the question-answer card framework to create new work opportunities for senior citizens. Our experiments showed that untrained seniors performed the micro-tasks effectively with our interface in both controlled and realistic conditions, and the differences in their skills were reliably assessed.