Mayan Astronomers used
Mathematics to devise a year of 360 days even though they knew that Earth's solar year is 365 days. 

The sun and Venus were of great
interest to the Mayan Astronomers
Because they were used them to measure the alignment of the planets.  Using this information they created the calendar.

Mayan villages were built on the inland.  Mayan cities were generally elevated stone structures surrounding the pyramids.  Mayan ceremonial temples were built atop the pyramids, in order to be closer to the Sun.

Mayan pyramids were built as
Observatories and a place of worship.  All Mayan dwellings were built
according to the Mayan's
understanding of the universe.

Instead of ten digits like we have today, the Maya used a base number of (20) They also used a system of bars and dots. 

The Mayans believed  blood sacrifice kept the cosmos in balance.  Women, men, and children were painted the color blue and then sacrificed by craniotomy; removal of the heart.  These ceremonies were held either at the top of the pyramids, or the temple courtyard.  It was an honor to be
sacrificed.