MARION, Mass. — With one set of grandparents on the West Coast and one on the East, my kids have seen the U.S. from the window of an airplane plenty of times.

This summer, we tried a lower-budget approach to our annual pilgrimage from Idaho to Massachusetts. We crossed the continent in our minivan, sleeping in campgrounds, picnicking at meals.

It did save money. Flying between Boise and Providence, R.I., and then renting a car for the six weeks we needed to be in New England, would have set us back about $1,200 for plane tickets and another $1,200 for an economy rental car — a total of $2,400.

With gas at about $2.60 a gallon, driving about 3,000 miles to New England in our 20-mpg Honda Odyssey cost us about $390 in gas. We aim to spend about the same amount on food as we would at home. Accommodation, of course, is all added cost; we spent $320 on that as well driving out. (While in New England, we'll stay with friends and family.) And we still have to drive back in August; assuming the same costs, the trip will end up setting us back about $1,400 for gas and lodging.

In all, we'll spend about $1,000 less on the road trip both ways than if we'd flown and rented a car. Depending on your budget, the savings might or might not be worth the trade-off in time. In our case, we had fun along the way. And we gained some unexpected wisdom and insight from our nine days together. Here's a summary, contrasting expectations with reality.

Driving: The plan

Our pre-trip planning led us to Route 2, the secondary road that winds across the northern tier of the United States. Staying off major highways, we reasoned, would help us avoid trucks and give us a glimpse of the real towns, businesses, farms and homes that make up our country. We estimated that we would need to drive about 300 miles each day to make it to southeastern Massachusetts within 10 days.

Driving: The reality

No sooner had we left Idaho than we abandoned Route 2, detouring to stay with an old friend who now lives in Deer Lodge, Mont. After that, we planned our route from day to day. Sometimes we took major highways; mostly we motored down the secondary roads. In unpopulated areas, you can travel those roads at 65

Camping: The plan

Accommodation would have made the trip more expensive than flying, so we planned to camp every night. We took as a guide the midsize Rand McNally Road Atlas of the United States, Canada and Mexico, which shows campsites on its

Camping: The reality

The atlas came in very handy, but some of the places we ended up camping in were state and city parks where we landed by chance after seeing a roadside sign.