Have a look at websites like this, and see if you can make them better. http://reliefweb.int/ Better means lots of things, but "easier to use with very low or intermittent bandwidth"; "easier to use for an international audience" etc.
Take the most important Wikipedia articles (where "importance" is about STEM education) and polish them into the very best they can be, with clear easy to understand text and nice examples and best diagrams. Translate these to different languages. (Whatever is used in areas that need them, so I guess Spanish, French, Portuguese, and whatever.) This might require a form from WP.
Investigate charities that do good work. Donate to those charities. Good work means different things to different people, but probably includes "doesn't spend too much of its funds on luxury offices and big wages" and "makes a change, doesn't just continue cycles of deprivation".
Research and promote low power computing. Most people have huge computers for what they actually do. Really, using social media, watching a few cat videos, and writing the occasional letter do not need gigabytes of RAM and 3 GHz quad core processors. Help with low resource Open Source projects. Never mind LXDE and XFCE, most people would be fine with JWM or IceWM. Moving people from 100 Watt desktop machines to 8 W arm (or similar) nettops would be useful for climate change.
There's bound to be some interesting but difficult to access research work around distribution - distribution of money and resources within organisations and from those orgs to the places where they're needed. Stuff crossing boundaries is an opportunity for loss. Those boundaries include geographical borders but also include regulatory boundaries for organisations. Visualisations of the journey of a donated dollar through the bureaucracies to the final endpoint would be fascinating, and possibly enraging, for many people.
Vote for people who don't do stupid things to developing nations.
Be careful when donating hardware to charity recycling. Often anything usable is sold off, with the junk being sent to places like the e-waste dump in Agbogbloshie, Accra, Ghana. Here's a programme and a clip about that dump. (http://www.bbc.co.uk/programmes/b00sch78) (http://videobam.com/rcEUM)
