For this project you will need salt, a glass of water, an ice cube and a string. According to Kids Science Experiments, the objective of the project is to lift the ice cube out of the water, using the above materials, without touching the ice cube or getting your hand wet. While it may sound like impossible task, you can accomplish it by first laying the end of your string on to the ice cube, and then sprinkling on some salt. The salt will cause some of the water molecules in the ice, which are arranged in a crystalline structure, to melt and break away from each other, forming small gaps where the string can sink in. When this water refreezes, due to the overwhelming coolness of the surrounding ice cube, it will trap the string in place. You can then pull on the other end of the string to life the ice cube out of the glass of water.
The objective of this project, according to iCollaboratory, is to determine what effects the exposure to freezing cold temperatures and the resulting formation of frost have on two different types of temperate plants: grass and lettuce. While you could simply pick some grass, buy lettuce from a grocery store, and then put samples of the two into the freezer, a better option is to grow grass and lettuce, and use the living plants as samples. Put each plant sample into the freezer, and observe and record any changes that take place over the next hours and days. Compare your results to determine which plant was the most resistant to the cold. You may notice that the lettuce succumbs to higher degrees of freezing, or rigidity, due to its higher water content.
For this project, you will be conducting tests to determine which substance can melt ice the quickest. According to the K-12 educational website, some possible test substances you can use include kitty litter, fertilizer, road salt, wood ashes and calcium chloride. Make a number of "ice pies" by freezing water in pie pans or other flat containers. The exact amount you will need depends on the number of samples you are testing. However, make sure to leave an extra ice pie to serve as a control. Pour a fixed amount of each sample substance on to its own ice pie, and observe which is able to melt the ice the fastest.