May 14

Parachutes

My fourth grade students were asked to design a parachute that would bring a load of their choice slowly and gently to the ground.

Engineers took this project through the Design Process:  Ask, Imagine, Plan, Create, Test, and Improve. They made the following design choices:

  • Canopy – size, material, and shape
  • Suspension lines – number of lines, material
  • Type of Load

They also had to choose a way to attach (such as tie, staple, or tape) the suspension lines to the canopy and load.

We compared the parachutes, explained and supported design choices, and discussed how problems were resolved.

As we dropped the parachutes from the second floor landing in the rotunda, classmates timed how long it took each parachute to fall approximately 18 feet.

Most loads hit the ground between two and three seconds, but the engineers in the photos below constructed parachutes that landed with times between five and eight seconds. When we returned to the classroom, we discussed why these parachute designs were more successful. Were there any similarities between them? Did the weight of the load matter?

Click here to view a video that we watched about drag.

Essential understandings from this activity include the following:
There are many ways to solve the same problem.
We can always improve upon our initial idea.
Sharing ideas with others helps all of us learn.
Engineering is a process.

We also looked at various ways parachutes are used from parasailing and hang gliding to slowing the speed of cars and space shuttles. Watch this additional use of parachutes:  Click here.

Watch below to learn how NASA developed a parachute for rovers on Mars.

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May 13

Mealworms

Second grade entomologists are studying invertebrates. We reviewed the body parts of an insect (head, thorax, and abdomen), and the stages of complete metamorphosis (egg, larva, pupa, and adult). At the lab tables, we observed mealworms which are not worms at all, but the larval stage of darkling beetles. Beetles are insects and insects are arthropods. Mealworms like all kinds of foods, and some of their favorites have the word “meal” in them. Click here to watch the metamorphosis of a mealworm.

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May 13

They’re Coming!

The cicadas are coming! The nymphs have spent 17 years underground, but soon a MASSIVE emergence of these insects will occur in the eastern United States. I experienced the invasion of the cicadas in Cincinnati the last time they arrived. It will be a sight that I will never forget! Click here to watch an informative video. Click here for additional information, including a map.

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May 12

Butterflies!

Kindergarten, second grade, and PreFirst classes were excited to watch the painted lady butterflies emerge from their chrysalids. If you haven’t watched this video yet, take a minute to watch the miracle of metamorphosis with your young scientist!  Click here. I order this product and other insects from Insect Lore.

A butterfly drinks nectar with its proboscis.

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May 12

Ocean Lab

I recently discovered this beautiful book and it’s perfect for teaching the names of shells. As I read the story, PreK oceanographers identified each shell on the grid. We also reviewed what we learned last week about gastropods and bivalves. If you enjoy trips to the beach, you will want to add this book to your library. Click here to purchase.

A peek inside:

Afterwards, we investigated which objects float and which sink. We discussed our thoughts first, but we were not in agreement. Do big, heavy objects always sink? Some of my scientists thought that flat objects float while those that are round sink. They all believed that objects with holes would sink. One scientist declared that objects with a lot of air inside float. As they chose objects, scientists supported their hypotheses, but we were often surprised with the results. When an outcome doesn’t match an hypothesis, learning occurs! Collect objects from around your house and test whether they sink or float in the bathtub.

Look at the objects below, form your hypotheses about which will sink or float and then scroll down to look at the results.

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May 8

Sundials

After a brief lesson about shadows, the compass rose, and the history and parts of a sundial, fourth grade scientists made a make and take sundial. Love the way this activity connects with angles. The toothpick is the gnomon. We investigated how a sundial works with a flashlight. The sundial must point to the North. Leave the sundial outside or in a sunny window to watch the passage of time. Click here to learn more.

May 6

Worms! Worms! Worms!

When you are studying invertebrates, you must include annelids! After learning about a worm’s life cycle, body parts, and habitat, second grade biologists investigated earthworms. We used hand lenses to look for the five hearts, setea (small bristles) that help the worm move, and clittelum, a band near the front of the worm where the eggs become cocoons. Worms don’t have eyes, but are sensitive to light and must stay moist to absorb oxygen. Because they are decomposers, they have an important role in the ecosystem. With two sets of muscles, the worms slid quickly across our trays. I demonstrated this movement with a slinky.

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