Lots of options but I will list them and you can read up on them by google or something.
(by the way you should enjoy the steam historic train)
Bonneville Dam and Locks with the sturgeon tank.
Fruit Loop in Hood River (exit 62 or 64)
Wineries there too. (Marchesi Vineyards just won in the September Sunset a great award for their Sangiovese Emma.)
Drive east on I-84 until you reach Goldendale and go across to Maryhill Park (and Museum and Winery) and drive east on SR 14 in WA until you get to Cascade Locks.
Have dinner at Multnomah Falls Lodge. Quite cozy and good food too, before or after you go watch or climb some of Multnomah Falls. At least climb to the bridge. Easy.
There is a tab on top of the page here that says Top Questions (or it may just be on the Oregon Forum.)