Use liquid laundry starch or soluble packing pellets in place of soluble starch.
Have students tie knots in the dialysis bags instead of using string.
Have each group do each solution in order to minimize class data error.
Do not use Glucose test tape as it will always test positive in the presence of IKI. Use Benedicts solution or test sticks to test for glucose.
Potato cores will be exactly the same length if you cut the potato first and then use the cork borer to make the cylinders. – Or the potato may be cut into strips of approximately the same size if a cork borer is not available.