Part-Part-Whole Thin Slicing

These task cards are a great way to turn a math lesson into a Thinking Task using the Thin Slicing technique Peter Liljedahl discusses in Building Thinking Classrooms. Thin Slicing is a systematic  way for students to discover new math concepts organically by moving through a series of tasks that gradually become progressively more complex in small, visibly random groups. In this model, students trade in each task card for the next one as they complete each thin sliced task.

The first few photos are designed to have a clear, logical way for students to sort the set, then subsequent photos offer students more and more choice for how they would like to sort the objects to increase the level of difficulty. Don't expect your students to finish the entire set, I only made this many cards to be extra sure we wouldn't be caught without anything for early finishers. I created this set to offer students an opportunity to practice using number bonds, but they could be used for many other lessons as well.

Several of these cards feature collections I made using the online version of KP tiles. KP tiles are my favorite math manipulative for how versatile they are and how effectively they capture the nesting nature of place value through grouping and ungrouping, and the online version is a great way to incorporate them in your classroom while you raise money for the real thing. As someone who has used this tool as a virtual tool a lot, my pro tip is that the blue square that covers the hundreds is much more likely to respond if you click on the darker circle at the center of the tile.

Finally, I would recommend copying this document and putting as many copies of each photo in a row as you need to print, because you can fit more on a page that way. Also, your groups will not all get to the later problems at the same time, so you don't need to print a class set of those photos. This is how many of each task card I printed for 20 students working in pairs:

1. Gummi Bears (10)

2. Mints (10)

3. Dogs (10)

4. KP1 (9)

5. Humans (9)

6. Eyeballs (6)

7. Eggs (6)

8. KP2 (3)

9. Stickers (2)

10. Gems (2)

11. KP3 (2)