In this easy, inexpensive experiment, students have the chance to witness density in two memorable and impactful ways! First, students combine colored water and baby oil to witness density – The oil and water separate because of their different densities. Then, the students drop a half an alka seltzer tablet into the bottle. This is when the fun really happens, and you will be sue to hear those, "OOOH" and "AAAHH"s! The alka seltzer releases carbon dioxide (a gas) which is less dense than both the water AND the oil, so the bubbles rise to the top. This reaction creates a lava lamp-like experience for the students. The kiddos LOVED this experiment, and still talk about it months later! The lab report below guides young scientists step by step through the scientific process to complete this investigation! This a an easy printable for teachers to follow, and the pack includes teacher instructions. I hope you and your students like it! Good luck!