We did SIG Bryn Mawr last summer when dd was 11. I make a point of mentioning the location because it seems that the SIG programs vary greatly from place to place. I did a lot of googling before we signed up, and many of the locations got poor reviews. Bryn Mawr generally had very good reviews, so we decided to give it a try.(We happen to be local.) In general, I thought the program was extremely well-run. The director of the program here was an extraordinarily credentialed and experienced gifted educator. Her resume was absolutely jaw-dropping. Not only that, but she seem to take her role so seriously. One little example – she personally met the drop off-line for the day students. So when you drove up and opened the door to hand your kid off, it was the director standing there with a clipboard saying good morning to you. The Dean of studies was likewise amazingly impressive.
As for course content, I would say that my daughter really enjoyed most of her classes. She took creative writing, a logic class where they solved mysteries, a finance class about the stock market, and a few others. In general, the coursework seemed genuinely engaging. For example, in the stock market class, they engaged in debates about social justice. The students in the class also created teams, and competed with each other to see who could earn the most money in a virtual stock market game.
It was only three weeks, but my daughter did make some friends. She left with the email of a couple of kids, one of whom was from Korea. She and this girl email back-and-forth a couple of times a week now, which I think is just so sweet.
Having said this, it was a very long day. Drop off was around 830, and I didn't pick her up until almost 6 o'clock. Sometimes, she had a few minutes of homework. The homework was never burdensome, and it certainly was never busywork. One night, the homework was to illustrate a cover for her short story. I think the intent was to keep everything fun. But she was sitting in classrooms doing quasi-academic stuff for many hours a day. I think that worked fine for us, because we homeschool, and so our schedule is much looser than for kids to go to school. So doing a more intensive schooley type thing in the summer wasn't such a big deal. But I will say that she has already decided that she does not want to do anything this summer! She definitely had a good time, and was glad she did it, but feels like it was really busy, and she's looking forward to more time off this summer.
Hope this helps.