Divide the room into different sections. This doesn't need to be done literally, but decorate the different sections or corners of the room based on the different areas of science. One area can contain things that represent life science, the other with items that represent Earth science and another can contain items that represent physical science. Use things such as the life cycle of a butterfly, a model of the layers of the earth or posters about sound waves and the three states of matter. The visual division may help students be aware of some of the different areas of science.
Determine an area for aquariums and living animals. Choose a safe place in the room where a class pet could be kept. The pet could be fish, a snake, hamster or lizard. Whatever the animal is, make sure it's something that's low maintenance and is safe enough to have around students on a regular basis.
Display things that will attract student attention. Crystals and rocks are things students enjoy looking at. Seeing the skull of animals they're familiar with is also interesting. Use different types of leaves, pine cones or tree stumps. Hang things on the wall such as life cycles, the scientific method, a periodic table, human anatomy chart or parts of a plant or flower. Also hang posters with the different categories of animals such as mammals, reptiles, insects and amphibians. Display a human skeleton if that is also available.
Use one wall for a word wall. Find border at your local school supply store and create a large outline on the wall to distinguish that wall as the word wall. The size of the area used for your word wall will depend on the size of your room. Each time a new vocabulary word is introduced, tape it on the wall. Seeing the words will help keep them fresh in students' minds. Classroom Jr. has printable bubble letters that can be used to create headings for the words "word wall" and throughout the room. Classroom Clipart also has printable clipart for various things such as the scientific method, weather and space.