I too have experienced students having a hard time with unplugged activities, however, as we talk about computer science being more than programming and trying to think as Computer Scientists - we look at the Computational Practices from p. 12 in the ECS Lesson book, the students are more open to unplugged lessons and broader concepts of computer science.
Computational Practices used in ECS
• Analyze the effects of developments in computing (impact/connections)
• Design and implement creative solutions and artifacts
• Apply abstractions and models
• Analyze their computational work and the work of others
• Communicate computational thought processes, procedures, and results to others
• Collaborate peers on computing activities