Just how small is a nanoparticle?


Leslie Ann Glinoga

Pascack Hills High School

Montvale, New Jersey


Columbia University's Summer Research Program for Science Teachers

Summer 2006


 This inquiry lesson is intended for use at the beginning of the year when discussing units of measurement, unit analysis, error, and significant figures.


 Students will be able to



1. Divide students into pairs or groups.

2. Provide each group with (a link to) a digital photo of a nanoparticle.

3. Instruct each group to determine the "actual" size of the particle shown in the photo and to show their work so others can follow what they do.

4. Some students will simply measure the particle as shown in the photo - remind them that the particle was magnified to make it visible.

5. Students will discover that they need more information to arrive at the answer- be ready to provide or help them find the magnification used in the photo and the number of pixels/dots per square inch

6. Have students write their proposed answers on the board.

7. Have each group explain how they arrived at their answer and whether they believe they are correct.

8. Take the average and discuss statistical outliers, error, and significant figures.

Possible Follow-up: 

Show/have students view "Powers of Ten" (video or online version). Have them pay special attention to the role of magnification and what can be found at the various levels.



Sample photo: Light microscope100X magnification



National Science Education Standards:

Content Standards A (Science as Inquiry)

B (Physical Science)

E (Science and Technology)

F (Science in Personal and Social Perspectives)

G (History and Nature of Science)