Hi Ursula,
This all sounds like a great way to teach about the planets. Using a variety of methods such as using large displays, books, games and building knowledge slowly over a period of time will really allow the children to interact with the lessons. I have definitely found when teaching about space in the past that you need to take it slowly with teaching about the planets as it is a lot of information to take in and can be overwhelming if you try to fit too much into your lessons. A fun art activity that we also did was where the children designed their own planet. This was completed after we had covered the planets and it was interesting to see the children draw on what they had learned to make their own planet.