I'm not sure what you mean by a "picture" of the appropriate color. If you just want to display the color, why not just use a color-filled rectangle? Also, is your dropdown on the worksheet (as opposed to a userform), and if so, is it a Forms dropdown (as opposed to a ComboBox from the Controls Toolbox toolbar)?
I feel this School project is a tad advanced if thats whats been asked of you to do ?? To acheive this would take some really very complex VBA and super line codes to do this, no teacher i expect would set this, assumes this is your own idea>
I cant say i know the answer but i do know and might be able to dig up code to place pictures JPG in comments boxes that would be possible to link to the value of a text box choice and the returned result behind teh box and make the comment box offset to the right .
Would this help... no promises if you are strong VBA minded and can program ill did the code out, its complex and if teh teacher asked you to explain the code you might fall down, and they will know its not your work!
im not really strong on the programming side of things, yes it was my own idea.. is it not possible to relay whats in the drop down box to another cell, and then use something to say "if "colour red" is in the <cell> then show this picture" or am i goin off on one?