This is a hands-on science experiment / exploration centered on density; however, it also includes division so it ties in nicely with math. The lesson explores sink and swim, while simultaneously teaching the density of various liquids. I taught it in a 5th grade class, but it could easily be lowered to a different grade level. It includes the objectives, standards (for Florida, but I list the description, so it should be easy to find the corresponding standard in your state), materials, and an in-depth explanation.
The objectives are : Students will determine that some liquids are heavier and therefore denser than other liquids of the same volume; Students will utilize balance scales to determine the density of various liquids; Students will use division to solve real-world problems to find the density of the given liquid; Students will predict and explain which liquids are denser than others.
The liquids examined are vegetable oil, corn syrup, liquid soap, water, and vinegar.
This is the first thing I am submitting, so I would love it if you reviewed it afterwards. I did not include the worksheets I created to go along with it since I am posting this for free; however, I discuss them enough that it would only take moments for you to create your own.