Grade 1 learning - measuring snakes

Bonjour!

Hope everyone had a great holiday season. We had a snowy return to school this week and have been starting to talk about and explore measurement, which will be our focus for the next few weeks. We are starting with length and have a problem where there is a zookeeper (un gardien/une gardienne du zoo) who is instructed to feed three snakes, starting with the longest snake first, and feeding the shortest snake last. The zookeeper doesn't know which snake is longest or shortest, so we have to help them figure it out. Here are les trois serpents (the three snakes):

The snakes are labelled A, B, and C (arranged as C, A, B in photo).

In order to get the snakes into the correct feeding order, students were asked to use string to help measure the snakes, then compare them to the other snakes. Here are some ways the students came up with:

Once students had an accurate string measurement, they were asked to compare their strings to other students who were measuring different snakes. They were then to check their work using non-standard units such as blocks, for example: 

This pair of students started by comparing their strings (masking tape added to mark the 'tail' of their snake), then each measured their own string with different blocks. We had an interesting discussion about the black blocks measuring 19 and the yellow blocks only measuring 13. Does that mean that the black block string is longer? Why or why not? This led us to the concept of the importance of comparing lengths using the same-sized units. We will continue with this work next week.