As mentioned by our host, most railroad museums rely heavily on volunteers and finding the next generation is a challenge.
Sumpter Valley Railroad will hold its annual Safety Weekend for pre-season volunteer training on Sat/Sun May 16/17 this year. See
http://sumptervalleyrailroad.org/ In addition, there may be one or two work weekends also some time in May (avoiding Mother's Day and Safety Weekend) this year. Several projects are planned including trackwork, painting and car repair that all could be quickly accomplished with just a few extra helping hands. Volunteers for train crews are becoming scarce, and anyone willing to volunteer one or two weekends a month (or more) has been able to fairly quickly qualify as brakeman, then conductor and on to the engine if they are interested. Since these are really small railroads, there is just as much need for anyone interested in track, crossing signals, locomotive and car maintenance and repair, buildings and grounds, administration, archives and the other 10 million things that always seem to be demanding attention. Locomotives in service will include Heisler #3 (wood burning, getting new flues for its 100th birthday party this year), SVRY 2-8-2 #19 and a GE 50 ton diesel-electric from Panama (similar to SPng #1). There are spots to park an RV and sometimes a bunk car or caboose is available, or there are motels and RV parks in the area at reasonable rates. Please check the website for more info.
Obviously if you don't live near the NE Oregon region, you may not be able to reasonably volunteer at the Sumpter Valley - but there is often some sort of railroad or depot museum within 150 miles of where you live that probably needs volunteers. Skills are welcome, but often just another helping hand willing to learn is just as valuable.