Parents want what is best for their children. Many parents will put forth great effort and expense to help their children excel in school, sports, or whatever pursuits interest them. Parents will also put forth great effort and expense to entertain their children--whether it is a trip to Disney World, iPods, iPads, X-Boxes, Netflix, etc.... None of these things is wicked in and of themselves. Parents have the right and the responsbility to take care of their children as they see fit.
Children are a gift from God. He does not owe them to anyone, but he blesses parents as it pleases him. Children are also the only gift God gives us in this world which we might see in heaven. Disney, i-devices, x-gadgets, and soccer trophies will not be there. They will neither be helpful nor missed when it comes to eternal life.
But parents sin against their children when they simply assume that they and their children will have a place in heaven. Parents may assume it because they went to church when they were younger. They remember the Bible stories they once learned, and they assume that their children know them too. Or they assume that their child's happiness is most important. And if soccer makes a child happy, then soccer is paramount. Or maybe parents have concluded that Sundays are for sleeping in (often because we intentoinally stay up late on Saturday). Somehow, this great need for sleep does not factor into Monday through Friday. Though children probably do not want to get up for school, parents will dutifully get them up, get them fed, and get them ready. They will even scold a whiny, tired child and say, "You're going to school. This is important!" On the other hand, no one demands that school start at 10:30 so that children can get the sleep they need. Instead, we put them to bed earlier.
But Jesus does not get priority. He is inconvenient.
I think it is safe to say that parents want to see their children in heaven. But if children are not taught God's promises, they will neither know them nor believe in them. Furthermore, children who are raised NOT going to church and Sunday School will learn not to go when they are older. If they are not raised in the church, they will not be faithful later. If they do not hear their Shepherd's voice in their younger years, they will not listen for it when they are older. This failure falls not just on the children who stray from the faith, but also on the parents who taught them by their attendance habits that Sundays were not meant for church.
The Lord Jesus Christ said, "Whoever is of God hears the words of God. The reason why you do not hear them is that you are not of God." (John 8:47) In other words, God's people listen to him, and his voice is heard from the Bible which is preached and taught every Sunday at church. Parents who do not bring thier children to hear and learn God's word sin against them by raising them to not be God's children. They will learn to listen to other voices. And even though listening to other voices might make the children happy, they will not lead them to heaven. Only Jesus does that.
I think it is safe to say that parents want to see their children in heaven. If this is your desire, then it must also be your desire and your duty to have your children grow in grace and in faith. To do that, they must hear and learn the story of salvation as proclaimed in the Bible. That is what Sunday School is for. (Such stories are also good for family devotions. If you are looking for a devotional book to use with your family, please speak to the pastor for suggestions.)
Sunday School attendance also teaches the children that Jesus and his Church matter. It is the responsibility of parents to bring their children up in the training and instruction of the Lord. The actions that parents take now will likely be the pattern followed by their children. I am not blowing it out of proportion to state that this has eternal consequences. Children are the one gift God gives to us in this world which we hope to see in heaven. No one gets there without Jesus, no matter how much you love them. And your children will not learn about Jesus unless you bring them to Jesus by means of Sunday School, church attendnace, Lutheran schools, and home devotions.
It may well be that your children will not want to get out of bed and get ready for Sunday School (8:45 AM--later than school starts). It may be that parents will find it drudgery to make Sunday School a part of the weekly routine. Satan will give you many reasons to skip. They will all sound good. But if you seek the eternal welfare of your family, you will put to death the excuses of your sinful flesh and make it a weekly habit to grow in the grace and knowledge of our Lord Jesus Christ. Parents can come to Adult Bible Class while their children are in Sunday School. Your weekly attendance will teach your children that this matters. Jesus will teach your children that they matter to him--enough for him to suffer and die to take away their sins and win them a place in heaven. That is paramount. Its value is eternal. And it is giving our children the best possible care that can be given.