Cut a piece of wick that is 8 or 9 inches long. Help third grade students tie the wick to a stick. The length of the wick should hang straight down from the stick when the stick is held horizontally.
Place a pot of water on the stove. Put another pot on top of it and place some candle wax in it. Turn on the stove and watch it until the wax is melted. Make sure there is sufficient wax in the pot so that at least 4 or 5 inches of a candle wick can be immersed.
Let third graders dip the wick into the wax. The wax will adhere to the wick. Have children dip the wick repeatedly into the wax by holding the wick over the wax while graspng the stick. Have them dip until the candle is about an inch wide at the bottom. The top of the candle will be narrower.
Place the candle on wax paper until it is completely dry. Gently pull the candle off the wax paper when it is dry. Use scissors to cut the excess wick, leaving the candle with a short wick of approximately 1/4 inch. Repeat the process until several candles are completed.
Freeze some of the completed candles the next day. Tell the third graders they are going to make observations about whether the candles burn differently when they are frozen. The teacher should light the frozen and room temperature candles using matches, so children can make observations.