I used this task in my 3rd grade classroom as an introduction to equivalent fractions. Students were given a visual, as well as a written description of 2 different ways that students split a pizza. The idea was for students to shade in fraction pieces and see that the 2 fractions were equivalent, however students were not told how to go about solving the problem. The task gives students a place to write their claim and argument, as well as a place to write what their partner thinks.
Microsoft Word version: 3_NF_FractionsEquivalence_ThinkPairShare_Critique
PDF version: 3_NF_FractionsEquivalence_ThinkPairShare_Critique