Hi anju Check ou this link..It contains project ideas for transportation model for kids Transportation Arts and Crafts Projects Ideas for Kids: Cars, Planes, Trains, Ships, Boats, Busses, Airplanes, Jets, Trucks, Canoes : Crafts Projects for Children Cheers Ramya
You can use Legos to make model size oblects like car, train, bus etc. Play dough will be another option. Again any mention of age group will be good for givingthe suggestions since the above two are for elementary grades.