A Tower Defense game is a great LiveCode project. You could use graphics (I mean the LC control type) to make paths or roads for enemies to follow, and transparent buttons with images for the characters. Buttons (transparent or not) could be used for the tower buttons. Then you add movements, timing, level objectives, and user interaction to respond to clicks or taps. I'm not sure how extensive your instructor wants it.
Some familiarity with LiveCode and with programming concepts will help, so the general LC tutorials and classes should be useful to learn the basics. Any game theory you've learned in class should be included too, for best results. But you may be in a hurry for this assignment! How much time do you have?
If you need any one on one tutoring or consulting, I always love a chance to work with people on LC games. For a class it's best to sling a lot of your own code and develop the skills. That gives you the most benefit, to put the theory you learn into practice with a little sweat. But there's lots of help available for learning LiveCode in one form or another, and I think you will enjoy making it.
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