Try organizing them knowledge sharing sessions. Do it in working hours, so you actually show it that's important for you that they learn.
You can also try organizing coding dojos.
Buy them books, or online library subscription.
You think I haven’t tried all this? It’s just their habit which is very difficult to change as they grow older.
When you say "my team", do you mean you manage them or you are their teammate?
I said, 'my employees', so I am not directly managing teams, but yes, in a way, I do manage.
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