I just turned 47. Wife + 2 kids. One in middle school, the other starting high school
I have a handful of strategies that have helped me get on a good track for retirement:
1 -Pay myself first. I look after the family finances. I religiously put an average of $25K away a year into the stock market. $750 every bi-weekly from my pay check and $5K annually into the kids education fund. I take the long view.....the dips in cash flow are addressed with a small line of credit, which gets paid back on a regular basis out of cash flow.....but I never miss putting the cash into the market
2 - Be cheap and let the family know you are cheap. Focus on cash flow, cut those monthly bills as much as possible. I think that for many people when the cash flow balance tips too far in the negative they give up and just embrace the devil of debt and give up on retirement planning. You have to break even on average AFTER paying yourself first.
I don't have an ipad....sure I'd like one, and I'm sure my 2 kids and my wife would like one too.....but creating an environment where frivolous spending is unwelcome helps. That being said, you have to spend on important things like family trips, adventures and making good memories. I drive a lexus RX400h...its a used 07' and cost me $10K. I own an 05' turbo mazda roadster. That cost me $12K. You can enjoy the good things in life...just be smart about it. My wife drives a new Mini (OK, I let my guard down on that one

).
3 - Invest in large dividend paying stocks (Banks, utilities, health care, etc.) Do it yourself and don't jump ship when things look shaky. Since mid 08' I've averaged 10~12% compounded annually by keeping it simple. Save, invest, hold (repeat).
My plan is to retire early. It will be weird still having a kid in high school and not working....but I need to stop working eventually for my own sanity.