+0
Example 1
A: You are a fine cook.
B: It's something I picked up/took up in school.

Example 2

C: I took up/picked up garding after losing my sight. It makes me feel useful and worthwhile.

What's the difference between the two phrasal verbs?

Thanks.
Comments 
Example 1
A: You are a fine cook.
B: It's something I picked up/took up in school.


Take up something - you make the decision to do whatever it is.

I took up golf when I was 11 years old.

Pick up something - to acquire a skill/knowledge without really deciding to do it or having to work/study/practice.

Example:

I live in Poland. I have NEVER studied the language, but I have picked it up.

So:
It's something I took up in school. - I decided to learn it/follow the course.

It's something I picked up in school. - I learned it whilst at school, but in a casual way.
Thanks, Optilang. Very clear!