As far as I can observe being a teacher, I am definitely happy that my students are involve in cryptocurrencies and they earn for themselves and help their families. But, their school perfomance is getting worse. Please give your thoughts how will you help students to earn and at the same time it won't affect their school works?
How do you know your students are involved in cryptocurrency? Where are you teaching, what do you teach, who you teach? I found it interesting that there are teachers who know about crypto and realized that their students also could be involved. I'm curious how involved are they in crypto? Are they just using it daily or also doing something else that took a lot of time. This could be the answer to your question. The reason your student's grades are failing maybe because they spend a lot of time in non-academic activities, such as crypto trading or mining or anything else so that they don't follow the class anymore. You should find out, talk to your students, and find a way out of it.