Description:

Students determine how fast a bottle will roll down a ramp with varying amounts of sand inside. They then predict how much sand is in an unknown bottle, and how fast bottles with different amounts would roll. The task assesses students' abilities to make simple observations, compare relative speeds, apply their observations and measurements to test an unknown, make generalized inferences from their observations, and apply their understanding make predictions.

This task is designed to take students approximately 10-15 minutes to complete.

Components:

• Administration Procedures
• Directions to the student
• Scoring Rubric
• Examples of student work
• Technical quality data

Overall Task Content Area:

Physical Science

Specific Knowledge Areas:

Motion and forces

Performance Expectations:

• conducting investigations
• gathering, organizing, and representing data
• formulating conclusions from investigational data
• Applying scientific principles to develop explanations and solve new problems

National Science Education Standards:

8 A SI 1: Abilities necessary to do scientific inquiry: Grades 5-8
1.4 Students should base their explanations on what they observed, and as they develop cognitive skills, they should be able to differentiate explanation from description- providing causes for effects and establishing relationships based on evidence and logical argument. This standard requires a subject matter knowledge base so the students can effectively conduct investigations, because developing explanations establishes connections between the content of science and contexts within which students develop new knowledge.

1.5 Think critically and logically to make the relationship between evidence and explanations. Thinking critically about evidence includes deciding what evidence should be used and accounting for anomalous data. Specifically, students should be able to review data from a simple experiment, summarize the data, and form a logical argument about the cause and effect relationships in the experiment. Students should begin to state some explanations in terms of the relationship between two or more variables.

(Use the "hot" link on the PALS home page to check the full text of related National Science Education Standards, if desired.)

National Council of Teachers of Mathematics:

COM2: Communicate their mathematical thinking coherently and clearly to peers, teachers, and others:
Grades 6-8

General Instructions to the Teacher:

Students will be working individually during this exercise.

Students should be ready to work as soon as the period begins. The materials should be set out at each lab station, if possible. A central supply area, if needed, should be easily accessible. All supplies should be clearly labeled.

Materials for "Sand in Bottles":

The teacher will need:

• white or construction sand
• plastic bottles with caps at both ends - size 148 ml
• hot glue

At this station students should have:

• 5 bottles labeled A, B, C, D, and X
• 2 books approximately 1 inch thick
• clipboard

Advance Preparation:

• Fill enough bottles for each student or station accordingly.
  • Bottle A - full of sand
  • Bottle B - 1/2 full of sand
  • Bottle C - 1/4 full of sand
  • Bottle D - empty
  • Bottle X - full of sand
• Bottles must be smooth so that they will roll down the clipboard easily.
• Slide a piece of paper inside each of the bottles so that the students cannot see inside.
  • Seal the tops with glue to avoid spills.
  • To make the bottles roll evenly - glue a cap on the bottom of the bottles as well.
  • Film containers will work if they have tops that push inside to seal.

Safety:

• Caution the students if glass bottles are used.
• Be careful.
• Teachers and students should always exercise appropriate safety precautions and utilize appropriate laboratory safety procedures and equipment when working on science performance tasks.

Extensions/modifications:

• Medicine vials or film containers can also be used.
• Any hard surface such as, fiberboard, smooth wood or cardboard may be used to create the incline.