Here are a few thoughts and suggestions.
First, many River or Stream Watcher organizations have good citizen scientist programs with trainings and mentors to help folks monitor waterway quality. Checking the Web sites of the ones in your region will let you know what they offer.
Second, the USA National Phenology Network is set up to help citizen scientists (or at least nature lovers who want to take their love of nature to the next level in a systematic way). In a nutshell, phenology is the process of watching and recording how species change over a period of time in relation to climatic conditions. The Web site
https://www.usanpn.org can explain in more detail.
Finally, the Weather Underground has a network of folks who have set up personal weather stations and feed the info to the wunderground.com Web site;
http://www.wunderground.com/weatherstation/about.asp
Hope this helps
Rob