Things To Do
Teotihuacán
Teotihuacan is one of the major wonders of the world, rivaling the pyramids in Egypt. This trip typically takes a whole day as it is in the outskirts of the city. Plan ahead, many websites such as Viator will do tours that will pick you up in the city. Please do not try to do this the day of the reception as you will not have time. Monday's are a good day to explore Teotihuacan as most museums will be closed on Mondays in Mexico City.
La Casa Azul
Frida Kahlo's House while she lived in Mexico City. Located in the scenic area of Coyoacan, Frida Kahlo's house is now a museum painted cobalt blue. This is one of the only attractions in the city that you will need to get tickets for in advance, sometimes up to a month in advance, due to its popularity. It is worth the trip.
Xochimilco
Mexico City was built on a lake, this is the last part of the city to still have that still has access to that water. Rent a boat and be paddled along slow moving water, while vendor boats sell you drinks, food, and mariachi boats offer singing/music. You are also welcome to bring all your own snacks and beverages including alcohol. You choose how long you want to spend on the water. This is not necessarily close to other parts of the city and will take a large portion of the day.