Dungeness: http://www.dungeness.org.uk/what-to-see/ Call the lifeboat station to see what time the boat is being launched, watch and then walk along the shingle beach. There is a nice cafe by the lighthouse at the steam train station.
Dungeness Steam Trains: http://www.rhdr.org.uk/ Take the train for a nice sandy beach a short ride away.
Rye Town Model: http://www.ryeheritage.co.uk/about-2/rye-town-model/ A visit to Rye is not complete without a viewing of the sound and light show at the Heritage Centre. Rye is one of the Cinque Ports and has winding narrow streets and the ancient town wall to explore.
Boduim Castle: http://www.nationaltrust.org.uk/bodiam-castle/ The castle has a proper moat and is a fantastic day out. There are often extra activities in school holidays for kids. There is a good national trust cafe and gravel paths suitable for most buggies.
Tenterden Steam Railway: http://www.kesr.org.uk/ You can have an extra adventure by taking the steam train from Tenterden and/or a trip on the canal!
Other National Trust within 20 miles: http://www.nationaltrust.org.uk/smallhythe-place/ http://www.nationaltrust.org.uk/lamb-house/ http://www.nationaltrust.org.uk/sissinghurst-castle/ http://www.nationaltrust.org.uk/stoneacre/ http://www.nationaltrust.org.uk/scotney-castle/
Leeds Castle: http://www.leeds-castle.com/home Enormous parkland with a huge play area for kids - but allow loads of time it is a long walk from the car park.
Dover Castle: http://www.english-heritage.org.uk/daysout/properties/dover-castle/ Surprisingly accommodating for babies and buggies.
Tenterden Leisure Pool: http://www.tenterdenleisure.com/tenterden/FAC_Pool Water slide, waves, and good area for small kids to play. Also a soft play and decent cafe at the leisure centre.
Things to see in Woodchurch: Woodchurch Windmill is visible from the cottage and worth a visit: http://www.woodchurchwindmill.co.uk/ Woodchurch Village Life Museum: http://www.woodchurchmuseum.com/ Rare Breeds Centre: http://www.rarebreeds.org.uk/ Local Pub: http://www.6-bells.co.uk/ Woodchurch Village: http://en.wikipedia.org/wiki/Woodchurch,_Kent
Camber Sands: http://www.discovercambersands.com/ Sandy beach with toilets & cafes only 20 minutes drive.
Whitstable: http://www.seewhitstable.com/ Longer journey and pebble beach - nearly an hour - but well worth it for picturesque English seaside.
Ashford Designer Outlet Centre: http://www.mcarthurglen.com/uk/ashford-designer-outlet/en/ Set in a large covered ring with a children's playground (also partially covered) and food court.
Ashford International Station for trains to London St Pancras and Paris: http://www.nationalrail.co.uk/stations_destinations/AFK.aspx
General information on the wider local area: http://www.visit1066country.com