A family-friendly Madrid plan balancing parks, palace exteriors, food stops, and short museum moments.

Retiro Park with its boating lake and open space is the easiest win for kids. Anchor the day there and orbit out to nearby sights in short bursts.
If you visit the Prado, pick a handful of paintings and a clear story, then leave. A short, focused museum stop works far better than a full circuit.
Lunch runs late and dinner later. Carry snacks, plan an afternoon break, and let the evening plaza atmosphere be part of the fun rather than fighting the schedule.