Density and Buoyancy word search, scramble and crossword puzzle

I made this density and buoyancy puzzle set for my 4th graders during our physical science unit. The kids could see a rock sink and a cork float but had no idea why. So I put together a word search, a word scramble, and a crossword using words like density, buoyancy, float, sink, mass, volume, water, oil, displacement, upthrust, dense, less dense, object, liquid, and compare. Nothing fancy — just puzzles to help the vocabulary finally make sense.

The PDF is four pages. Three puzzles plus one answer key page. The word search works well for quiet time after recess. The scramble gets them talking because they argue about why a heavy ship can float but a small rock sinks. The crossword I use for partners. I added a couple simple drawings of objects floating and sinking in water but nothing too busy.

Works for 4th through 5th grade. Print and go. Sometimes I have early finishers explain why ice floats on water on the back. The kids actually ask for these now.