Weathering and Erosion for Kids: Break, Move, Drop (Grade 4 Science)

Hi, I'm Luna from DoodleBeez. Mountains look like they last forever, but they are slowly changing. Rock breaks, moves and settles somewhere new. Today we will learn about weathering, erosion and deposition.

Weathering is when rock breaks into smaller pieces. Water can seep into a crack and freeze. Ice takes up more space than water, so it pushes the crack wider, until the rock splits apart.

Plants can weather rock too. Their roots grow into cracks and slowly push them apart. Wind blowing sand can also wear rock down, a bit like rough sandpaper rubbing a surface.

Erosion is when the broken pieces get carried away. Moving water, wind, ice and gravity all move rock and soil. Rivers are strong movers, carrying sand and pebbles downstream.

Deposition is when the moving pieces are dropped in a new place. When a river slows down near the sea, it drops its sand and mud. Over time, this can build new land called a delta.

Over very long times, these changes shape whole landscapes. A river carved the deep Grand Canyon, and giant glaciers carved wide valleys in the mountains of British Columbia.

Now it's your turn. Water freezes in a crack in a rock and splits it into pieces. Is that weathering, erosion or deposition? Pause and try. It is weathering, because the rock broke apart!

Great job! Remember, weathering breaks rock, erosion moves the pieces, and deposition drops them in a new place. Together they slowly shape the land. Practice weathering and erosion in the Science Lab at doodlebeez.com. See you next time!