I would personally recommend Assisi Catholic College. I find the students there to be respectful and well behaved and each student I have encountered has enjoyed their time making memories at this lively and enjoyable school. Although there are many competitors (CAC, St Stephens, UCSC) I believe that Assisi tops them all.
Whatever you do avoid UCSC at all costs unless you want your kids to be beaten up and bullied or roaming the streets like mini gangs. I'd probably looks at schools at helensvale or private schools in the area.
Coomera Anglican is a great private school with big ovals and in a close vicinity of all major highways and Coomera hub. There is also st Stephan's but I personally think Coomera Anglican has a better criculum.
Ucsc would be the best choice for public as its queenslands largest public school.