Train in from Zurich or Geneva, check everyone’s winter gear, then walk the Höheweg and the Höhematte meadow at dusk.
Day 2
Snow school
Children’s ski lessons or the practice area at Bodmi in Grindelwald, then hot chocolate and an early night.
Day 3
Jungfraujoch
Go on the first clear forecast: Eiger Express from Grindelwald Terminal, the glacier views, the Ice Palace and the Snow Fun Park.
Day 4
Sledging day
Up to Männlichen or First and sledge down; or the gentler Niederhorn run above Lake Thun.
Day 5
Lauterbrunnen & Mürren
Staubbach Falls in winter, then up to car-free Mürren and, if the sky is clear, on to the Schilthorn.
Day 6+
Lakes and cities
Bern’s arcaded old town and its mosque at the House of Religions, or Thun’s castle and the winter boat on Lake Thun.
Honest thought: mountain weather decides everything. Keep the Jungfraujoch, Schilthorn and First flexible and use webcams each morning; on cloudy days choose sledging lower down, Bern or a chocolate workshop instead.