One of the easiest and most appealing aquarium craft ideas is a paper plate aquarium. This craft is easy to assemble with inexpensive and readily available materials. Cut out the center of a paper plate and fasten a sheet of clear plastic on the inside of the plate. On a second plate, paste blue construction paper or allow the kids to paint it blue. Attach green aquatic plants. Then add construction cutouts of different fish, an octopus and perhaps a seahorse or two. Adhere the two plates together for a wonderful little display.
The clear plastic containers that hold berries such as strawberries are ideal for a small aquarium craft. Normally tossed away, this is a project that teaches children about recycling. Construction paper, tape, markers, thread and scissors are all you need for this craft. Have your children design a series of waves or a blue backdrop to place on the back of the container and tape into place. Then using string and a bit of tape, suspend fish, seahorses, divers - whatever comes to your children's imagination - out of construction paper. Close and jiggle slightly to give the cutouts a bit of animation.
For a group project, make a cardboard aquarium. Find a sturdy cardboard box, cut out the center of one side and use spray paint to color the remaining frame black. Use clear plastic and cover the cutout area to resemble an aquarium's glass surface. If you can find it, use clear blue sheeting for the back wall of the aquarium. Then cut out various pieces from cardboard that resemble fish, aquatic plants, rocks, or anything else your kids would like in their aquarium. Using some thread and tape, string these items from a clear plastic sheet that you can fit over the top of the aquarium frame. This project encourages teamwork and can be displayed in your classroom.
If you are looking for a project that will make a more prominent display, then consider making and constructing papier mache fish to fit within a large diorama, such as an oversized box made to resemble an aquarium. Take liquid starch, newspaper strips and a balloon. Blow up the balloons and carefully wrap it with the newspaper strips after they've been dipped in the starch. Be careful not to cover up the balloon's tie. Allow these to dry suspended from a coat hanger with a clothes pin to keep them in place. Then paint and decorate with craft supply eyes and paper plates cut to resemble fins.