Fourth:

We choose different places in our school to measure air pollution in each then we write our conclusion

Required Materials:

• White posterboard (paper plates could also work)

• Scissors

• Hole punch

• Magnifying glass

• String

• Vaseline

• Permanent marker

• Notebook

• Pencil

Procedure:

1. Find an area in which you can hang several cut out pieces of

the poster board. You can perform this experiment in your home,

yard or another area of your choice depending on where you

would like to examine how clean the air is.

2. Cut the poster board into several 3x3 inch squares.

3. Draw a square with the marker on each cut out piece of poster

board, a little smaller than the square itself.

4. Punch a hole in the top of each piece of poster board and tie

pieces of string in the holes so you can hang the cut outs in the

area of your choice.

5. Smear a thin layer of Vaseline inside the drawn square on each

cut out and hang them in different places within the area you’ve

decided to examine. Record the areas you’ve hung each cut out

in your notebook.

6. Wait 6-10 days to collect your squares and examine your

results.