1. In 1780, Massachusetts ratified its state constitution, making it the oldest functioning written constitution in continuous effect in the world.

2. The first American zoo was founded in Boston on May 5, 1876. The facility was called the "Boston Zoological Gardens," and it was later renamed the Franklin Park Zoo.

3. On May 5, 1961, astronaut Alan Shepard became the first American in space when he piloted the Freedom 7 spacecraft. Shepard's spaceflight lasted just 15 minutes, but it paved the way for future space exploration.

4. May 5, 1970, marked the beginning of a student strike at Boston University, protesting the Vietnam War and the invasion of Cambodia. The strike lasted for several weeks and led to clashes between students and police.

5. On May 5, 2004, same-sex marriage was made legal in Massachusetts, becoming the first U.S. state to legalize gay marriage. The landmark decision was based on the state constitution's equal protection and due process clauses.