I'm a big fan of using models to demonstrate science concepts. When students can visually see a concept, it makes it significantly easier to understand. For example- if you ask students about the components of the atmosphere, they tend to think oxygen is the most abundant. Here is an easy way to show them which gas is the most abundant in a very visual way!
Legos can be used in a lot of different ways to demonstrate science concepts. You may be thinking that Legos are expensive, but that's only if you buy Lego brand or special kits. They sell off-brand Legos at Dollar Tree, and you can also find used Legos at children's stores. (You can also bug your friends with older kids to donate their old sets to your class).
Once you have a collection of Legos to use, divvy them up into containers. Again, hit up the dollar store. Purchase enough Tupperware containers to have one kit per group (I tend to break my class into 8 groups, so I have 8 kits). Dollar tree also sells the flat Lego baseplate you can build on. I hot glued them onto the top of the Tupperware so students can build directly on the container and hopefully pieces don't get lost. They also stack easily in the cupboard this way.
Alright, so you have your kits built and ready to go. Now what?
Here are some ways you can use Legos to model science concepts:
1. ELEMENTS, COMPOUNDS, MIXTURES: What is the difference between elements, compounds, and mixtures? Have students model the difference between the three.
2. CHEMICAL REACTIONS: Teaching chemical reactions? Use different colored Legos to represent different elements. For example, blue is oxygen, white is hydrogen, etc. Have students build molecules and show a chemical reaction. Are the number of atoms on the product side of the reaction the same as the number of atoms on the reactant side?
3. MIT CHEMICAL REACTIONS: MIT has created Lego chemical reaction activities that use different colored bricks for different atoms. Check out their website that has activities for photosynthesis, atmosphere, ocean acidification, and chemical reactions. These lessons are AWESOME, but the only drawback is they use very specific pieces.
4. PRECIPITATION TOWERS: This NASA website uses Legos to model weather data. (Note: This specific lesson is for younger grades, but could be modified for middle school).
5. STOP MOTION MITOSIS: Provide students some lego "chromosomes" and have them create a stop motion video showing the process of mitosis. The more pictures the better! To turn the pictures into an animated video or gif, try apps like iMovie, stop motion studio, or videoshop.
6. AGE STRUCTURE DIAGRAMS: Provide students with population data and have them create a scaled age structure diagram out of Legos.
7. TROPHIC PYRAMIDS: Provide students with a food chain, and have them create a pyramid of numbers and a pyramid of energy or biomass for that particular food chain. A great way to visualize the different types of pyramids!
8. LIQUIFACTION: How do soils affect the stability of buildings during earthquakes? In this activity, students build a tower out of Legos and test the stability on different types of soil. Maybe you have some budding structural engineers in your class!
9. PLANET SIZE AND SCALE: Provide students with data on the size of the planets in our solar system. Have them create a scaled model of the planets- a great way to sneak in some dimensional analysis!
10. DNA REPLICATION: Check out this blog post from Science with Mrs. Lau on how she uses legos to model DNA replication!
11. K&P ENERGY: If you have wheels and axles in your Lego tub, have students build Lego cars and measure the amount of kinetic and potential energy they have as they roll down ramps.
I hope your students have fun building!