How has work done aboard the International Space Station improved life for Earthlings?

That’s debatable. We’ve learned how to spend a lot of time in space. We’ve found that sugar will coagulate itself thus giving us some insight into how rocks and dust in space might cohere to start the nucleus of a planet’s development. We’ve discovered that bone density decreases drastically in micro gravity. We’ve had some great photos. We found out you can play a guitar in micro-gravity. We’ve spent a whole lot of money, and continue to spend $5 billion a year just to maintain it. We plan to take it apart if nobody wants to buy our share and de-orbit over the ocean. Was it all necessary? The space shuttles were the most disastrous space program ever. More people died than ever before, burning up on launch and burning up on reentry. Now we hitch rides with Russians. It’s very pretty to see it go overhead – a big bright white dot racing across the night sky. Did I mention it’s debatable?