There are always surprises.

The hot-button issues that typically get cited before the start of each session - taxes, education, jobs and the economy - will surely be part of the conversation again when the Washington and Idaho legislatures convene today.

But they probably won't be the most talked-about items by the time lawmakers head home. Every year there's something new, some unforeseen controversy or dramatic event that dominates the headlines and lends its special flavor to the session.

That's partly what makes these annual gatherings so addictive: Legislative sessions are like the Cracker Jack box with a prize hidden inside, an ever-changing story, antidote to boredom and the daily routine.

Who could have predicted, for example, the success Idaho Democrats experienced last session - in an election year, no less - when a string of top Republicans quietly acknowledged the wisdom of their views on issues ranging from legislative ethics to state employee compensation?

Similarly, how shocking was it when three Washington Democrats jumped ship in 2012, snubbing their own caucus to join Senate Republicans in passing a more conservative budget? The move presaged the bipartisan "majority coalition" that continues to rule the Washington Senate to this day.

No one could foresee such events. So as the 2015 sessions begin, here instead are four simple things - some important, some merely interesting - to keep watch for. Place your bets on whether any will still be part of the conversation come April, when lawmakers prepare to adjourn.