I loved the skills I was able to learn during this internship and the exposure I got to the world of academic economics. I learned a lot more about how to assess the quality of a dataset and how to answer economic questions. My workplace also had a lot of young people all thinking about potentially applying to grad school, so I learned a lot from them about the different graduate programs in the area as well as about the lifestyle of an economist generally. My workplace also held biweekly lectures and I got the opportunity to study in greater depth the interesting papers real life economists are writing.
What I wish was different
I think the work got lonely at times -- especially in a setting without a big research team. The other RAs were somewhat older than me, so I found it difficult to find friends in my workplace.
Advice
There were a great bunch of Wellesley alumni at the NBER I didn't meet until my very last week -- I would encourage you to reach out to them, because I really enjoyed talking to them. In general, don't be afraid to reach out and get to know people there!