US Commemorative Quarters by Theme Quiz

Answer: Minnesota

Minnesota's quarter has a swimming Loon.
Other iconic, but not necessarily official, state birds are the California Condor, the Louisiana Pelican, a Peregrine Falcon in Idaho, a South Dakota Pheasant, an Oklahoma Scissor-tail Flycatcher, and a South Carolina Carolina Wren.

Answer: Maine

Maine's quarter has a three-masted schooner, based on the "Victory Chimes," off the coast.
Other notable vessels are the English ships "Susan Constant," "Godspeed" and "Discovery" bringing the settlers to Jamestown, Virginia; George Washington crossing the Delaware in New Jersey; Lewis and Clark on the Missouri; the 1903 America's Cup winner "Reliance" on Narragansett Bay in Rhode Island; a Spanish galleon off Florida and two Minnesota fishermen in an outboard.

Answer: Vermont

The Vermont quarter has two Sugar Maples on it.
Others with trees as a major design element are the Charter Oak of Connecticut, the Palmetto of South Carolina, the Palm of Florida and Oregon's conifers.

Answer: Delaware

Delaware, "The First State," has Caesar Rodney astride the horse he rode 80 miles to cast his vote for independence.
Kentucky, of course, has a thoroughbred, Nevada some Mustangs and Wyoming a bucking bronco.

Answer: Nebraska

Nebraska's quarter has a covered wagon pulled by oxen.
Some other prominent animals are Alaska's Grizzly Bear, one or more Bison on Kansas, Montana and North Dakota, Wisconsin's dairy cow and Washington's King Salmon.

Answer: Illinois

Abraham Lincoln is on the Illinois coin. Others are Caesar Rodney on Delaware, John Muir on California, the Minuteman on Massachusetts, Washington and his troops crossing the Delaware on New Jersey, four presidents at Mount Rushmore on South Dakota, the Wright Brothers on North Carolina (though Orville is a little hard to see), the bronc rider on Wyoming, the maple sap collector on Vermont and King Kamehameha on Hawaii.
New Hampshire's "Old Man and the Mountain" may or may not qualify.
I was going to say the astronaut on Ohio's quarter might be either man or woman, except the design description emphasizes "Apollo" era, when all such were men.

Answer: Alabama

Helen Keller is on the back of Alabama's quarter.
Pennsylvania has Justice from the state capitol dome, New York has the Statue of Liberty, Iowa has a woman, perhaps a school teacher, planting a tree and Nebraska's covered wagon has what appears to be a woman and girl.

Answer: Utah

Two train engines depict the completion of the transcontinental railway on Utah's quarter.
Nebraska has the covered wagon mentioned here already, Indiana has an Indianapolis race car, North Carolina and Ohio both show Wright Brothers Flyers and Florida shows a space shuttle.

Answer: West Virginia

West Virginia's quarter shows the New River Gorge Bridge.
Rhode Island has the the Newport Bridge on Narragansett Bay.
Missouri's Arch of Discovery, or St. Louis Arch, comes close.

Answer: Vermont

Behind the maple trees on Vermont's coin stands Camel's Hump Mountain.
California has Half Dome in Yosemite Valley, South Dakota has Mount Rushmore, Colorado has sort of a generic Rockies depiction, the "Old Man Mountain" on New Hampshire and Nebraska makes its third appearance in this quiz with Chimney Rock.
I hope this was fun to play and I would welcome comments.