At last week’s gathering of people who want to see light rail used to further economic opportunity for all, a demographer named Manuel Pastor described the difference between the game of chess and a jigsaw puzzle.

I wasn’t at the meeting, but Pastor has made the analogy before, and I found it easily on the Web. The comparison, Pastor said, came from a community organizer in Sinaloa, Mexico. The short version:

“In chess, some pieces are far more important than others. In a jigsaw puzzle, every piece is important because you need it to complete the puzzle. In chess, you get ahead by kicking someone off their territory and taking it over. In the jigsaw puzzle, you make progress by putting the pieces together so you don’t know where one ends and the other begins …

“We have been playing too much chess and not enough jigsaw puzzle,” Pastor said. “We have been pitting the rich against the poor when we are all in the same complicated environmental, economic and social puzzle, and we have been dividing ourselves by race and generation when we have together just one future.”

In the Sun Valley neighborhood, the beginnings of just such a jigsaw puzzle are underway. On Tuesday, the city held its second public meeting on the future of this neighborhood, which is the state’s poorest and home of Sports Authority Field at Mile High.

FasTracks’ West rail line — with its Sun Valley station — is scheduled to open next year. With light rail comes development. The question is what kind.

“Imagine you were the mayor, with no problems and unlimited resources. What would you do in Sun Valley?” asked Barbara Frommell, a senior city planner with Community Planning and Development.

She tells me Sun Valley is the most exciting project she’s worked on.

“They have real problems that we can actually start to resolve over the next couple of decades. There is so much opportunity to make good things happen,” she said, “and we have a huge team working on this.”

Music to my ears. I won’t rehash my Sun Valley series, but it’s worth remembering that in addition to being the state’s poorest neighborhood, Sun Valley is also the city’s most isolated. It is the community that few know exists, tucked east of Federal Boulevard, south of the West Colfax viaduct, west of the South Platte River — yes, that’s it behind the Zuni power plant — and north of the West Eighth Avenue industrial belt. Nearly all residents live in Sun Valley public housing. Most important, this is a neighborhood of children. Almost half of its population is under 18. For at least 25 years, the city has recognized the harm it has done to residents who live here.

City leaders now appear to be taking their responsibility to Sun Valley seriously. This is the optimistic view. It is not necessarily shared by all who live here. Residents want a better quality of life. They fear what they may have to give up in return. This is not unexpected.

One good sign is that the city has set aside its first draft transit-oriented development plan for the neighborhood. The Denver Housing Authority and city said it was not comprehensive enough. Residents believed it once again turned them into an afterthought.

A more comprehensive plan is being developed, and the city and DHA are employing extensive, multilingual community outreach.

“What will make the future bright?” read the fliers that went out to residents. At the meeting, they were given small cards representing different types of housing, businesses, civic institutions, community gardens and other amenities. They decided where each should go: next to the river, stadium or light-rail station, or along Federal Boulevard.

Conversations were lively.

“I’m really pushing for the families who live here to be able to stay and work here, but a lot of them don’t have the skills or education, so we need to address that.”

“The stadium should be an entertainment district, but we’d like to keep the river to ourselves, and development should be limited there.”

“The school has to remain the center of this community.”

“I’m not opposed to mixed-income development, but how do we make a community like this without gentrification?”

Everyone likes to dream, and it was an afternoon of optimism tempered by skepticism. The light-rail station has opened a door to this neighborhood. Challenges loom. Opportunity awaits.

Tina Griego: 303-954-2699, tgriego@denverpost.com or twitter.com/tinagriego