There may be many fun games for kids over internet but coloring pages from Disney story books have no substitute. They can be provided by school teachers as a fun activity too. But you also need to award your child when he is done with the coloring. Kids need appreciation and it can be done by encouraging them through rewards.
So prepare ahead of time and make sure that you've got enough distractions for the kids so that the trip will be uneventful in terms of fighting. Siblings don't usually like sharing stuff so you'll need at least two of everything. Two sets of crayons, two sets of coloring books. And it's probably best to make sure that both sets are exactly the same so that they don't get into an argument over the perception that Billy's coloring book is better than Casey's.
You need to keep in mind that color-by-number printables are designed for kids, who've got certain problems with the learning process and diligence. Many moms and dads have valued the evident pros that these coloring pages can offer. The main positive aspect of color by number pages is that these materials turn the whole process of learning into an enjoyable activity. Therefore your daughter or son will study the ropes of maths when coloring different images.