There are many sources for datasets and statistics that you may want to incorporate into your projects. Below are just a sampling of sources that may be found online. Most are freely available except where otherwise noted. The sources on this page are not intended to be a comprehensive list, but rather a starting point for your research.
World Development Indicators is a compilation of internationally comparable statistical metrics related to global development and the fight against poverty. The database contains time series indicators for more than 200 countries and over 40 country groups. Data for many indicators spans more than 50 years.
Compiled by the U.S. Census, International Statistical Agencies provides links to the official statistical agencies for countries of the world (note: some sites may not provide content in English). Scroll to the bottom of the page to see the full list of countries. Free resource.