Does some one know Top 10 popular locomotive in US? or popular locomotive for kids.
If you'll rephrase the question, I think you'll get some response. Do you mean the top 10 tourist railroads? Top 10 model locomotives? Top 10 seen on TV or in books? (Thomas has a monopoly there) What age are the kids you have in mind?
I mean not TV character. It is popular model locomotive. If I give as gift to kids in US which locomotive model makes them happy?
I'd ask the parents. the answer would depend on what scale/gauge/manufacturer they have now, whether they want to stay with that or move on to something else, the age & dexterity of the kids, etc. It may not be possible to get the correct answer from this forum because we don't know the kids. That said, it's nice of you to want to do something nice for them.
If the kids like trains it probablly won't matter if it is a steam locomotive or diesel-electric locomotive.
Small children may need a large scale train. LGB and Bachmann make large scale trains, as do others.
If they are very young, age 4-5, they might like a Thomas the Tank Engine trainset.
HO scale should probably only be given to an older child or one that can handle and take care of the smaller model size.
Growing up back in the late 50's early 60's, between the ages of 7-12, I had a set of Atlas "HO" scale diesel-electric EMD "F" series type locomotives and rolling stock.
For Christmas each year, I have a cheap all-plastic large "G" scale Bachmann trainset that runs on batteries that I place around the foot of my Christmas tree. The locomotive is a 4-4-0 "General" steamer, and it has a tender, passenger car, tank car, and caboose. It runs on plastic rails. If something breaks I won't be out of a lot of money. It cost me $40 15 years ago.