We could make it a mission to plant as many trees as possible. This is actually fun, brings more beauty to communities and country sides, and is really inexpensive, especially when you coordinate with volunteer groups, churches, schools, etc. Trees are one of the greatest consumers of CO2 and also exhale that wonderful O2 we all crave. It's so easy to set a workable goal around this concept and it would give the current and future generations a bit of pride in making the world a better place. No technology here, just good old fashion agriculture.
Certainly solar is making a lot of impact in many areas of the country and world. Let's continue down that path with more and more ambitious goals. I really think we should be pushing for more solar cells on just about everything we use. The technology is there and even if it just gives us miniscule results, it would help offset a large amount of energy on a global scale.
Encourage community gardens and local farmers markets. This is a win-win in so many ways. Communities taht garden together can share the abundance of their resources. They'll also spend less time purchasing produce packed in plastics, which is a sad trend that is occurring right in front of our eyes (why two tomatoes need a protective platic barrier around them is beyond me).