Ideas for Science Investigative Project

I have come up with a list of ideas for the SIP (though nearly all of them are unacceptable):

1, Investigate how the change in pH or temperature of coke affects how much coke/the speed at which coke spurts out when a mento is put in. This would investigate, I think, how the amount or the pressure of carbon dioxide in the coke is affected by the independent variable. However due to high expenses and the amount of resources wasted, the idea is not accepted. (However, now I come up with an idea to measure the amount of coke that comes out by channeling it to a measuring container, so it will not make a mess and easier to measure, and determine the pressure by measuring the speed at which the coke reaches the container. Still, it does not solve the expenses problem, really a lot of coke is needed.)

2, Investigate in what ways detergent is harmful to different things. this idea is still quite undeveloped because I wanted to investigate things as I want to investigate about how detergent harms human hands. Because human hands cannot be used for the experiment, I was thinking to use plant parts (epidermis) that has similar physical characteristics as the human skin. But the substances on plant epidermis are really different from those on human skin. I have to do research about what substances in detergents exactly damages the skin.

3, Other ideas: which type of food attracts the most ants (my mother does not allow this as I want to do it at home; at any other place it would be hard to monitor closely and constantly.) Another idea is the effect of temperature on the rate that corrosive household chemicals corrode. But upon second thought, it might be too dangerous.

So now I need to do research about detergents and human skin. However, so far my research has turned up nothing yet.....