You can avoid almost all the scrambling bits on the North Ridge. One of our daughters did it when she was nine, However, it obviously depends on your son's inclinations and abilities,
I find that not dwelling on the difficulties, but just saying "It's a scramble" works for my three. If they find things awkward, I show them how I would do kit then climb behind them to reassure them. Note this only works if you child is relatively light compared to you, I wouldn't try this with my son now!