Here are my tips on what to do in & around Cape Town
Table Mountain take the Cable Car up at sunset bring a bottle of wine and have a sundowner as the South Africans call it while watching the sunset
Gondwarda Game Reserve was amazing. Its a 4 hour drive from Cape Town and a bit pricey but a once in a lifetime safari experience with the ability to see all the Big 5 and many other animals and they also have a pool to relax at lovely accommodations with great views & good food. Kids under 12 can't go on game drives but they do offer babysitting. You can also walk in the safe zone and see giraffes and other animals up pretty close
Stay in Stellenbosch we enjoyed both L'avenir & Eikendal Lodge where you stay on working wine farms. Eikendal supports a cheetah program so if you ask about it they may give you free passes to go pet cheetahs at a reserve which is very cool and usually costs around $20 a person (they gave us 2 free passes)
Have lunch Le Petite Ferme in Franshhoek great food and an amazing view of the whole wine valley. Babel also has an amazing lunch but you have to book 2 months in advance They are located at Babylonstoren Winery which I highly recommend they have some great wines
Drakenstein Lion Park is also cool and is near the Winelands all lion rescues and if you go at 4pm you can watch them feed the lions I think on Mon, Wed 7 Friday
World of Birds in Hout Bay is great if you like monkeys and birds and tortises all are rescues and kids would like it!
Robertson Wine Valley is beautiful and they have some great wines to try
Go on a township tour very interesting and educational and they will take you to eat at Mzoli's in one of the black townships which has amazing BBQ
Dash Restaurant in the Queen Victoria Hotel on the Waterfront has amazing food we had the best dinner of our trip there very high end but not very expensive
Cape of Good Hope cool to see & stop at Boulders Beach along the way to see penguins up close and personal
Hermanus is a quaint town and during Oct & Nov you can see whales from the shore or go on a trip on a boat. We stayed at High Season Farm a working cattle farm with self catering houses its not too expensive and you can cook your own food and also see Hemel en Aarde wine region lovely with great wines. Try the food & wine pairing at Creation Wines they have one for kids too that's not wine of course
Robben Island the prison tour was cool with a former political prisoner the bus tour before kind of a waste
Enjoy, Cape Town really is a great place to visit!