Authentic Problems: Bottle Flipping


This unit for Year 3 is one of a set of ten units in the special topic “Mathematical Inquiry into Authentic Problems”. Each of these units is designed around the 4D Guided Inquiry Model, and highlights the importance of students providing mathematical evidence. The lessons adopt a carefully designed pedagogy to help students master content knowledge whilst learning about the process of inquiry. 

The inquiry is stimulated by a question: What fraction of a bottle needs to be filled with water to be the best for bottle flipping?

Bottle flipping is a popular game. Students decide what unit fraction of a bottle to fill with water to improve its chances of flipping easily. They work in pairs to devise a way to collect and record data, organise the data into categories and create displays to support their findings. Their displays may include lists, tables, picture graphs and/or simple column graphs, created with and without the use of digital technologies.

Read the Teachers' Guide (also included in the download) before using this resource.


Lesson 1: Discover Phase

Students are introduced to the context and the inquiry question: “What fraction of a bottle needs to be filled with water to be the best for bottle flipping?” They brainstorm what they know about bottle flipping and see it done. The mathematics of fractions is reviewed and students describe the amount of water in the bottles using fractions. Students experiment informally with flipping different bottles and various amounts of water.

Lesson 2: Devise Phase

Students begin recording a plan to answer the inquiry question. They determine what “best” means in the inquiry context, acknowledging that a fraction of water in the bottle is a key consideration. Students practise flipping bottles with various amounts of water, and in different size and shape bottles, before seeking feedback on their initial ideas for a fair test and for systematic recording of results.

Lesson 3: Develop Phase

Students use feedback to adjust and improve existing evidence before continuing their data collection and systematically organizing their evidence.

Lesson 4: Defend Phase

Students prepare their justified solution to the inquiry question and provide feedback on others’ presentations, focusing on the mathematical evidence used. Students reflect on the feedback given to determine what they did well and what they could do to improve their results and presentation.


Last updated May 22 2018.