Quick explanation for a 7-year-old: ostriches are very big and heavy, so their wings can't lift them into the sky. They run super fast instead. Here are four playful ways to say that:
- Ostriches are so big, the wind can't give them a lift!
- Ostriches are giant feathered sprinters, not flying birds!
- They're too heavy to fly, so they zoom along the ground instead!
- Ostriches are like big, fluffy cars: feet for running, not wings for flying!