What is an invention that I can ';make up'; and draw for a presentation in science class?

I made a confetti shooter made from pneumatics that was really quite simple. I took a tri-pod and i attached the container part of a syringe to it. Then i took a pump and tubing provided by my school and attached it to the small part of the syringe. The syringe would be where you put the confetti or in my case glitter. The stand makes it adjustable too. You have to use a lot of tape to insure no air escapes and then its done! For extra marks make an advertisement for it. I hope it makes sense...What is an invention that I can ';make up'; and draw for a presentation in science class?
depends what yourstudying

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