This lesson is to be used after asking and telling age in the target language has been presented to the class. It can be used a review or as an activity to reinforce the language.
The first step is to randomly give your students numbers, this is to represent the age that they are. (if you have a large class you may want to have two sets) Then the person who is one year old will start off. They will say, "I am one year old, who is two years old?" Then, whoever has the 2 card will stand up and say, "I am two years old, who is three years old?" You go through the class once, and then repeat and challenge the students to get faster and faster. It is also a good idea after the second time to switch up the numbers.
To assess this activity, I check for participation and effort during the activity. Then, at the end of class, they have an exit ticket. On the ticket they have to tell you how old they are and ask you how old you are.