I did two weeks about 20 years ago when I was about 18/19 - I'd got a parking ticket a few weeks before and initially thought it was something to do with that
Boss at the time signed saying I could attend but couldnt return for a part day so they had to pay me for the full day everyday I turned up (I was on a silly low paid YTS scheme at the time and my big boss said I'd I did a part day to go in and he'd pay me as well

)
First day being shown round / sworn in was quite interesting but then sat about for the rest of the day, bored stupid. People had taken books and stuff to pas the time - I took nothing and this was well before smart phones or even really mobile phones so had to blag papers to keep the boredom at bay.
Second day started off the same but was, mid morning, called up for a suspected burglary case. It was blatantly obvious they were guilty as sin and was wrapped up in two days.
The next day I was called up for a murder case which lasted the remainder of my service and, from the off, most the jury thought he was guilty. During the course of the trial the deceased`s partner gave evidence which essentially resulted in the guy being found guilty of manslaughter and walking out due to time served. The same statement also resulted in her realising (whilst being crossed examined) that her actions had, probably, ultimately killed herb boyfriend
It was quite eye opening and frustrating at times. Most things were well explained but some of the debate and comments from some of the jurors when we retired to consider our decision was downright scary.
I think its a good thing for people to see the justice system in action, good and bad.