You can always let your kids do fun activities with you. On their birthday if they are old enough, you can have a train birthday cake decorating activity. It will be a fun bonding activity for you and your kids. Instead of just buying them a birthday cake, you can let them do their own cake. You can let them knead the fondant or make designs for their train. Aside from spending time together, you can also teach your kids a sense of responsibility. You let them be responsible for a task while you guide them. There are also lot things that they can learn while doing this activity such as measuring, heating, mixing and the like. But above all, you can give your kids a sense of accomplishment once they know that they did something for themselves.