A pass worked out great for me this year. At Kirkwood. It was about $489 for the pass, good every day this season. In addition, for 5 tickets on weekends I get $10 off (that's $50 in savings). Weekday tickets are $45 with the pass, that's $22 off per ticket, unlimited use.
This year, so far I've put in 13 days at Kirkwood (might go tomorrow). At regular prices, $871. My wife went 8 times, 3 were midweek. Regular prices that's $536.
So, I've so far saved $382 on my tickets and $116 on hers for a total savings of $498.
Season pass worked out real well for me.
Your results will vary depending on ticket prices, pass prices, and the number of days there.