Focus on one experiment that determines what solutes will dissolve in water. By using a combination of salt, baking soda and sugar, you can have the class record the time it takes the same amount of each solute to dissolve in water. You must ensure that the water is the same temperature and that the same amount of each solute is placed into the water. After recording how long it takes each solute to dissolve, you can discuss why one solute dissolves more quickly than or slower than the other solutes. This experiment is a way to introduce students to chemistry.
Using the same solute, such as salt, you can show that the temperature of the water can affect the solubility of that solute. Take three different beakers of water and ensure the water in each is at a different temperature. One can be colder than room temperature, one can be room temperature and the other can be warmer than room temperature. Add the same amount of salt to each beaker of water and record the time it takes for the salt to dissolve in each beaker. This experiment will show the students that the hotter the solvent, the quicker the solute will dissolve. You can discuss what temperature does to the solvents and solutes.
Measuring how much solute can be dissolved in water is another water solubility experiment. Take a scale and measure a large amount of a solute, such as sugar, and add this amount to a pint of water. Stir in a small amount of the measured sugar until all of the solute is dissolved. Measure out a smaller amount of sugar and add it to the beaker of water. Stir until it dissolves. Continue adding smaller amounts of sugar until the water will no longer dissolve the sugar. Subtract the weight of the remaining sugar from the total weight. This amount will tell your students how much sugar can be dissolved in a pint of water.
A saturated solution is the maximum amount of solute, such as sugar, that dissolves in a certain amount of water. Use three or four different solutes, such as salt, baking soda and sugar and perform the measuring experiment for each solute. Record how much of each solute will dissolve and cause the water to become a saturated solution. You can discuss why more or less of each solute can be dissolved.