Investigation One introduces students to the concept of density. Through observation and experimentation, students will learn that different liquids and different solids have different densities. Students will use volumetric equipment to combine two different liquids and to combine liquids and solids. Their observations will enable them to realize that matter that has a low density will float above matter that has a higher density.  

In Investigation Two, students will calculate the density of water. Students will use volumetric equipment and a triple beam balance to obtain measurements of different volumes of water. Students will then use a mathematical formula to calculate the density of water. Students will discover that the density of water is a constant value of 1 g/ml. Their measurements and calculations will enable them to realize that if the mass and volume of water are changed, the density of water will not change.

During Investigation Three, students will compare the densities of three different liquids. Students will use volumetric equipment and a triple beam balance to obtain measurements of different volumes of each liquid. Students will then calculate the density of each liquid using a mathematical formula. Through their experiments, students will conclude that different liquids have different constant values. They will also come to realize that when the mass or volume of any liquid is changed, the density of that liquid will not change. 

Investigation Four gives students an opportunity to explore the density of five different solid objects. Through measurement and calculations, students will calculate the density of each solid. Students will discover that the volume of each solid can be measured by the use of a mathematical formula or by the volume displacement method. Their observations will enable them to realize that solid matter has a constant density that is dependent upon the mass and volume of the solid, but that different solids have different densities. 

In Investigation Five, students will have an opportunity to investigate the density of solutions. Students will create a 20% and a 45% salt solution and compare their densities to the density of water. Students will perform a simple test that will compare the density of an acrylic cylinder (solid) to the density of water and to each solution. By observation and experimentation, students will come to the understanding that the density of water will increase as more solute is added. 

Investigation Six consists of a performance assessment designed to evaluate students’ understanding of the science concepts addressed in the first five Investigations of the Core Experience. During this exploration, students will use the knowledge they have gained about the density of solids, liquids, and solutions to design and test an undersea city.