Make NGSS come alive with this 5th grade science story about ancient tombs, vanishing mummies, and the mystery that matter doesn’t actually disappear. Aligned to 5-PS1-2, The Case of the Disappearing Mummies is a narrative science lesson that blends Egyptian history with physical science. Students investigate what really happens when things like mummies, candles, or puddles seem to “vanish” — and why it proves that matter is conserved. This Story: The Case of the Disappearing Mummies Standard