If your students can figure something out by themselves, let them.
Too often, teachers give a lecture and take all the fun out of the process of discovery.
Teaching about Hubble's classification system for galaxies is a good example.
Instead of giving the Galaxy Lecture or the Worksheet about galaxies, do this activity instead:
1. Give each small group a set of cards with photos of the different types of galaxies. Have them "play" with them, moving them around on the table. After they are somewhat familiar with the cards, you'll notice they naturally start separating the cards into groups. Encourage any group to do this if they don't start on their own. Once they have them separated, ask them to make labels for each group. (Give them blank squares for labels.) Don't offer any suggestions. Many will know some of the names, such as Spiral, etc. Just let them know it's okay to use the correct term if they know one.
2. Have each group share their system. You might have different arrangements and it would be good to discuss the differences. Just make sure they all know they did a good job! No wrong answers!
3. Then show them Hubble's Classification System! Hand them the Hubble Tuning Fork card. Have them rearrange their cards using the Fork card as a guide. Give them the correct terms and have them redo their labels. An extra pat on the back for those who came close!
4. Fun time to show a PowerPoint on Galaxies, or a YouTube clip. For BONUS POINTS, they could number a piece of paper and record the name and type of galaxy for each slide. Or you could make this required.
By the end of this lesson, your students show be able to identify the type of Galaxy when given a picture of a galaxy.
NOTE: Email Marcia for a Dropbox download of my complete Galaxies Lesson!
