The rounding roller coaster is a great way to help students visualize the rounding process. I laminated a few copies so my students could write on them over and over with dry erase markers. Simply fill in the number you are rounding in the correct box (ex: add a 3 in front of the 2 to make 32). If the roller coaster stops at 32 would the carts roll back down to 30 or to 40? I left room on both sides of the number so you could round to the nearest hundreds too. My students LOVE using the rounding roller coaster and I hope yours do too!