Germany's challenge: How will schools absorb thousands of Syrian children?

To hear their Syrian parents tell it, Yasser and Taha, ages 6 and 9, were the driving force behind the family’s decision to make an arduous overland trek across half of Europe to reach safety in Germany.

“School for them, a good education — that is the most important thing there could ever be for me,” said the boys’ father, Zaid Taha, a businessman from the contested Syrian city of Aleppo. He led his family’s exodus after a barrel bomb fell near their home, killing next-door neighbors.

“Education, that’s their life,” he said, laying one hand on each boy’s head. “That’s my goal. That’s my heart.”

An enormous influx of migrants and refugees — 20,000 people crossing into...