Next week is national fishing and boating week and most states have a free fishing period (no license required) during that time. Check your state's DNR or DFG website.
California is Saturday, June 11.
Many others are June 11-12.
Take a kid fishing and have a blast, then, go back and buy a fishing license so you can keep it up. It's a win/win situation.
http://www.nationalfishingandboatingweek.org/