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How The Constellations Change With The Seasons
For thousands of years, man has looked up to the night sky and seen shapes in the stars. These figures aren't actually there, of course - the stars we mentally connect to make them appear aren't necessarily where we think they are. The stars which make up the cup of the Big Dipper, for example, are light years closer or farther away from us than they appear to be. They certainly do not make a neat scoop shape; they only appear to do so from our perspective.
This perspective changes, however. As the year progresses, the seasons change, as a result of the orientation of our planet relative its parent star, the Sun. The revolutions of our planet around the Sun also cause the night side of the Earth to constantly change which direction it faces. This change is what causes the stars and constellations we see during the seasons to be different. During the summer, the stars that we see during the winter months are hidden behind the sun, undetectable by the naked eye during the day.
An easy way to go about understanding how this works is to set a lamp in the center of an empty room. The lamp is meant to represent the Sun. Now, imagine that the walls are covered in stars. If you're standing in the room facing away from the lamp, then your shadow is the "night sky". If you walk in a circle around the lamp, then the spot on the wall you are covering with shadow will change, just as the observable night sky for the Earth changes as it revolves around the Sun.
Of course, what you will see in the sky depends on where in the world you are. People in the southern hemisphere will see some different stars than someone in the northern hemisphere, and most of the stars which they both see will be seen at different times during the year. This is due to the tilt of the Earth's axis. Just as this reverses the seasons between the hemispheres, it also has an effect on what stars can be observed on any given night.
Interestingly, the Earth was not always tilted as it is today. Over hundreds of thousands of years, the tilt of the Earth's axis changes drastically. This would have a dramatic affect on what stars and constellations would be observable from any given point on the planet. The "shapes" would not change, of course, merely where you would have to be to see them; the stars would not be changing position, but the Earth's orientation would change, thereby altering the point from which you would be observing the constellations.
Having a telescope can certainly work to bring you a greater appreciation for what it is you're looking at. With good enough equipment, the spherical nature of some celestial bodies can become far more apparent than they are with the naked eye. However, constellations do not require that. All we need are the small points of light on a clear night, and the ability to connect the dots - something even a child can do.