Hi. In science, we are doing a project. We have less than 4 weeks to complete it. In this project, we must INVENT something. We are only on year 7 and are not capable of inventing a teleporter. Please list some simple inventions that Haven't BEEN INVENTED YET that we can make? This is a reall hard thing, but please. Thank you so much!

Why not just look at doing something already available in a slightly different way.
Not all inventions are completely original or group breaking..

Look at Apple for example.
Steve Jobs didn't invent anything, he simply had a knack for repackaging and selling Cool.

Baseball cap with built in ear phones for listing to IPOD.

I can't find one anywhere, I just got a IPOD, ( OK not on the cutting edge) but I wear a ball cap and hate ear buds, I have a great headset but does not work well with a ball cap.