Arrange train carriages according to numbers on their sides. The numbers are represented in a range of formats such as words, numerals, base-10 blocks or counting frames. Identify the numbers that come before and after starting numbers. Work with whole numbers up to 20. For example, arrange four carriages into the order 8, 9, 10, 11. This learning object is the second in a series of five objects that progressively increase in difficulty. The series is also packaged as a combined learning object.