There are several ways to catch smelt. By far the easiest is to not shower for a few days. The next easiest is to invite B~C over to your house in March sometime. Make sure you have plenty of freezer space.
The way B~C gets the smelt is by assigning his students the task of bringing them to class. I think they get extra credit for them.
The smelt make their yearly run in from the ocean to spawn this time of year. Ours come up the Columbia River headed for any of many smaller tributary rivers. A couple of hot ones are between Longview, WA, and Portland, OR. To catch the critters, you take a small meshed net with a real long handle and dip them out of the river. I think the limit is 10 lbs. per person per day, and when they are thick, you can get that in just a couple dips. One sure way to find where they are is to head for the flock of seagulls that are on the river way inland.
Several years back, before DEQ made us put in a $30 million intake screening system at the paper mill on the Columbia, we could get lots of smelt out of the sump at the water intake house. The guys had made a large stainless steel basket with no top that they lowered into the sump on ropes. As soon as it hit bottom, they would pull it back up. When the smelt were thick in the river, the basket would be full by the time it reached the surface.
A lot of folks eat the things. My dad used to fry them heads, guts, fins, feathers, and all. He ate most all but the head, too. Made me sick to watch him. I have tried them fried, but only after they were cleaned. They didn't seem good enough to me to bother cleaning too many. Now all I want them for is sturgeon bait. And B~C's institutional smelt are by far the best we've used. And using his smelt helps the young adults, too. Shoot, there are kids from Ken's class that can't even spell their names, yet they are state certified diesel technicians. Just thinking about that makes me regret buying the Cummins Dodge.