text: what can i use to build a model roller coaster in two days?   you can buy a roller coaster kit at most hobby stores. the most popular are the ones by miniature amusements, knex, coaster dynamix, and imaginarium. some of the kits are challenging, but a lot of fun when you finish them. i had the most success with the knex roller coaster kits - lots of fun! do a yahoo search under any of those names to get more information. good luck and have fun!