In order to improve the society, one needs to be a good citizen first and listen to what heart says because heart has the ability to empathise. Be kind towards everything that surrounds you, including animals, trees, humans etc.Educate others about whatever good you know. That you u can serve the society.
Lower the population. This is a global problem, not just an American one. The world has over 7 billion people in it, America has over 320 million. We are using up our natural resources are a terrible rate. Everything from fresh water to woods, farmable land, fisheries etc. are being depleted. Less people mean less usage. It will take decades, probably a century or more, but we should work toward reversing this trend. Bring the world back down to 3-4 billion and America to 250 million and things would be much better. Those numbers are just a rough guess.
Enact new laws for a more transparent government. Currently, laws are not written by the legislators. They are written by corporate lawyers and by extremist groups such as ALEC. We need to change that. Put law making back into the hands of elected officials and force them to put their name to any bill they write.
Related to point 2, America needs to change the way it passes bills. No more sudden changes late at night by small committees. No more adding provisions that are not the subject of the bill.
More education. I have severe doubts that 4 years of high school are enough. The world is a more complex place than it was 50 or 100 years ago. People are living longer too. I suspect a 5th, even a 6th year of basic HS education is required.
Clean up contaminated sites. Corporations have been dumping toxic chemicals into the environment for ove 100 years. We need to hold them accountable and start cleaning up the environment at a faster and better rate than before. A lot of work has been done already, but much more needs attention.
The economy is unstable. Banks and "Wall Street" manipulate the markets and cause collapses while the rich get richer and run off blameless for what has occurred. We must institute more controls so events like the 2007-08 crash doesn't occurr again. If a bank fails, fine, but it shouldn't take the nation down with it.
Fund NASA to unprecidented levels. Among the things Americans are most proud of is the nation's space program. Landing on the moon, sending probes to Mars, Jupiter and Pluto, the Hubble telescope, and so on. However NASA is in decline. Personally, I would like to see it brought back to glory.
New power and communications grids. America is behind the times with regards to how energy is moved and shared across the nation. Granted, it's a big nation. We can and must do better. Same with the Internet. Practically every other developed nation has a superior Network compared to America's. That is shameful.