Each group needs:

• (optional, for the Introduction/Motivation activity) ~8 beads of three various sizes (total number of beads can vary)
• 250-ml beaker
• Observation Handout, one per student or per group
• Data Collection Handout, one per student or per group
• colored pencils or markers, for sketching observations

Depending on the group assignment card and class size:

• 4 groups each need 1 strip of dialysis tubing*, ~10 cm (teacher to pre-cut and pre-soak in water for 15 minutes so that students are able to open it to load with testing molecules), pipette, and 1 piece of 10-cm long embroidery thread, string or yarn
• 4 groups each need 1 zipper sandwich bag
• 4 groups each need a 30 x 30 cm piece of plastic wrap
• 4 groups each need a plastic grocery store bag (with no holes)

*One source of dialysis tubing is Fisher Scientific’s 10-ft (~3-m) roll of size MC-18 seamless cellulose dialysis tubing, which is 25 mm flat width x 16 mm open diameter for $11.50 at https://www.fishersci.com/shop/products/seamless-cellulose-dialysis-tubing-16/s25645.

To share with the entire class:

• (optional) various household items to use as building supplies for the Introduction/Motivation activity construction of “selectively permeable membrane” models, such as boxes of various sizes (such as cereal boxes and other assorted food boxes from home), cardstock, plastic grocery store bags, tape, rubber bands, funnels, paperclips, disposable plates and cups, etc.
• scissors
• 6 1,000-ml beakers, for preparing and storing the following solutions:
• iodine solution: 500 ml of water with 10-20 drops of iodine
• corn starch solution: 500 ml of water with 3 grams of corn starch
• food coloring solution: 500 ml of water with 5-10 drops of food coloring
• blue marker dye solution: 500 ml of water with 7-10 blue markers (such as Crayola Washable Markers) turned upside down in the water
• yellow marker dye solution: 500 ml of water with 7-10 yellow markers (such as Crayola Washable Markers) turned upside down in the water; note: if the class size is 24 or fewer students, the yellow marker dye solution is not needed (thus, groups 13-16 cards and lab procedures are not needed)
• 1,000 ml of tap water

• Assignment Cards, one printout to be cut apart into 16 cards (one card per group)
• Testing the Selectivity of Common Polymers Lab Procedures, one printout to be cut apart into 16 separate half-page instructions (one section per group)