how important is the extra activities for the 11plus exams , for example music, elocution etc.
We have reach a grade 2 in music and thinking of stopping now as there is a lot of work on the academic side.
Unless you are applying for music scholarships at independent schools, the music lessons are of no direct use when it comes to the 11+. However, is your DC merely having the lessons because they are 'useful', or does s/he actually enjoy them? I would also ask yourself whether an academically selective school is the right place to be aiming for, if the only way to get there is by abandoning everything not directly related to passing the entrance exam? All the grammar schools I am familiar with are justly proud of the extracurricular activities and achievements of their pupils, both in and out of school (and don't see sport, music, drama etc as being a hindrance to academic achievement - they expect their pupils to be able to do both).
If you and your DC are sure that the 11+ school is the way to go, then please have confidence in him / her and don't give up all the fun things