Get a special stamp card and find the stamp stations to get a special item. The 2020 Museum Day event is May 18 through May 31.
Find the Stamp Stations
In your museum, the bug, fossil, and fish galleries each have three stamp stations. Check on each one to get a stamp for that gallery's stamp card. If you get all three stamps, you get a prize for that gallery. There are three prizes, one for each gallery.
After you get all three stamps from a gallery, talk to Blathers to get the completion stamp and your prize: a plaque for that gallery. There is a fossil plaque, a fish plaque, and a bug plaque. Be sure to get all the stamps in each gallery to get all three prizes!
More Stamps Each Day
The stamp stations are available each day during the event, and may be in different locations from the previous day. You can get stamps every day, and talk to Blathers to get additional copies of the bug, fossil, and fish plaques if you wish.