One-hour covered canal cruise to get an overview of Amsterdam's historic canal belt — warm and relaxing for kids; many operators run 9:00am–9:00pm in winter.
Powerful, compact museum — book timed tickets well in advance (museum typically opens ~9:00am–7:00pm in winter); suitable for older kids (consider the subject matter).
Walk around Notre-Dame (exterior) and visit Sainte-Chapelle (stained glass; open ~9:00am–5:00pm) — both are compact stops that fascinate kids with glasswork and history.
Book a late afternoon/evening slot (tower open ~9:30am–11:45pm) to see the city lights and enjoy less daytime cold; pre-book elevator tickets to avoid lines.
If kids are up for walking, view the Arc (top open ~10:00am–10:30pm) or enjoy window-shopping and seasonal decor; consider elevator access for strollers at Arc if needed.
Full-day admission to Disneyland Paris (parks open ~9:30am but seasonal hours may be extended) — perfect for kids; pre-book tickets and FastPass-type options where available.
Climb or take the funicular to Sacré-Cœur (basilica open daily) and enjoy panoramic views — charming neighborhood with painters and small shops kids often enjoy.