Science Labs

Having students do activities leads to long term learning and problem solving. When I worked for a bank in their wholesale lockbox, they spent maybe 30 minutes describing how to do the job. But the bulk of the training period was doing practice transactions. I trained at a grocery store before it opened, we pretended to scan and complete purchase transactions. Almost all jobs I have had, I learned on the job.

As teachers, we learn on the job. It's no surprise that so many people leave during the first five years of teaching. Some of the lessons we have are truly miserable. Working with the public is no picnic. Factor in children who don't have the maturity or home life to be good students and you can have some pretty rough days.

One thing I learned about activities is that it engaged students in the learning process and the classroom was easier to manage as a result. I know some folks swear by the worksheet. It does keep the kids quiet and you can do much instructing. What it does not do is expand process skills, help students explore the interaction of variables, or produce lasting long term learning.

Activities help students understand the concept. However, general knowledge about the subject is communicated. My next blog will be an activity on teaching about the layers of the Earth's atmosphere. Students scored well on the test and I did not lecture or use questions over the text. Instruction with lecture, questions over text are legitimate ways of teaching to combine with guided learning activities.

How do you manage labs to get the most out of students.

1. Break up labs into small pieces whenever possible. Spend 20 to 30 minutes doing an activity and spend the rest of class doing other activities. When I used lens with a light unit. I would spend 5 to 10 minutes with a lab activity several days in a row.

2. Have students complete steps together. This way you do not have one set of children finished and dawdling while another group decides to pack it away and just copy the other group's answers.

3. Provide enough materials so all children get to do the activity. I taught at an evening high school. It was eye opening when I introduced a lab. The students sat there and just looked at first. They had always been in groups where they were the passive participants.

4. Never allow students to just do the lab. The physical change lab with ice cream is an example. I always had students to do one step before I passed out the materials for the next step. I would ask questions and monitor progress between steps.
One time in summer school, I did the same lab with another teacher who used the free for all approach. I understand teenagers should be able to work independently. It was just a big sloppy mess with little learning. All my work gathering materials for the students to just plunder through, the personal cost of milk, sugar, etc lost.

5. Do the activity before you teach a concept not as a reward afterwards. Students will learn the concept more readily.

6. Use cooperative learning judiciously. Make sure students work as a team and not have a divide and conquer scheme or one or two children in the group doing the lion share of work.

7. If you feel uncomfortable with the safety or procedure of an activity. Delay or don't do it if you are uncomfortable. Your sub-conscience is speaking.

8. Live within your budget. One thing that people learn as teachers, that you will spend your own money. It is the cost of doing business. Some teachers will monopolize equipment. One time I had a class set of thermometers. Someone took them and they were not there for me to use. I know they thought the school bought them. I had bought them. Choose how much you will spend and stick to it. Look for low cost activities. It's amazing what can be made or created at a lowered cost.

9. Anytime a student does something that could injure themselves or others, stop the lab and remove the student. As an educator, our job is to teach students. On the most basic level, our job is to send students home each day safely.
This story is hearsay and I'm sure the facts are generalized. A teacher was using alcohol burners to do an activity. Two boys were tossing a lit burner. The teacher told them to stop. They continued when her back was turned. One burner sloshed alcohol on one student and it burned the student. The teacher lost the lawsuit because they did not have control of the students. In essence  she should have stopped the class and removed the students.

10. Think about information you share with students and other adults.

I stopped telling students about eating poke salad when I took a class outside to learn the names of common native plants in the area. I realized a student was too curious on how to cook it. Poke salad can be very poisonous if you don't pick it just so and you have to drain the water you cook it in several times. People in the mountains of North Georgia ate it after a long winter. Supposedly if you ate 8 messes a year, you wouldn't get sick. More appropriately, the vitamin C from the green leaves probably prevented scurvy. Poke salad is a food of basic survival which hopefully most children will not have to eat.

There are some educational activities that I will not share on this blog. I have no idea whether the teacher would use discretion doing the activity. I wouldn't want someone hurt.

11. Choose safe activities and substances in the first place. Its amazing what can be taught using vinegar as your acid, etc. If it produces a noxious byproduct that cannot be disposed in a landfill or down a drain. Keep looking.

Resonance

A five year old demonstrated this to me on a front porch with a jelly jar. The jar did not fall off the railing but I do suggest using a wine glass. The cheaper, the better it will resonate.

Use a wine glass because you can hold the glass by the stem. When I taught school, I got quite a collection at yard sales. Do warn children to not go home and use mom's fine crystal. One child broke an expensive wine glass at home doing this.

Directions:
1. Partially fill wine glass with water.
2. Dip index finger in water.
3. Rub the rim of the glass with finger until the glass vibrates. It makes a pleasant sound.

4. You can have students compare the sound of different wine glasses and different water levels.

Making Waves with Sound

I remember the first time I taught sound, I repeatedly found references to making a crude drum to demonstrate vibrations. There is so much more to do. The following are my favorites to do when studying sound.

Feel the Vibration.

Give all the students a balloon. Give them time to blow up the balloon and tie the ends. Have students hold the balloons by their fingertips. Read a poem or other short text. Vary your speech from soft to loud and back to soft. I would read the children's book, "Moses Goes to a Concert" by Isaac Millman. Let students share what they felt.

A percussionist, Evelyn Glynnie who is profoundly deaf has played for the London Symphonic orchestra  She experiences music through its vibration.

It's important that students know that there are three types of waves.

Sound is a mechanical wave which must have matter to travel. The moon has about 25 moonquakes a month. If there were matter between the Earth and Moon, the Moon would ring like a bell.

Sound travels faster through a solid than a liquid or gas.

In Westerns, on television, the cowpoke and native americans put their ear to the ground to hear horse hoofs and people in the distance. Wyatt Earp the legendary lawman had terrible arthritis and joint problems from laying on a
ground at night.

There are two ways to demonstrate this.
1. Tie a length of string to a spoon. Give students different lengths of string or instruct them to cut different lengths. I used yarn but twine will do.
2. Have students wrap the free end of yarn around a finger and insert the finger into the ear. Actually touching the concha of the external inner ear with the finger.
Diagram of external ear: Use figure 904 for reference.
3. Standing and Bending from waist with the finger wrapped by the string and touching the interior of the external ear, have students allow the spoon to tap against a chair, desk or other inanimate object. They should hear a very loud sound.
4. Have students remove string and finger from ear and allow the spoon to tap against the same object.
5. Ask question, Does sound travel better through the air or the string and your finger?
(Children will want to say, the air) Prompt them, where was the sound louder? When your finger was touching your ear or not touching your ear? When they tell you when the finger was touching your ear, repeat the question, does sound travel better through the air or the string and your finger and more of them will get the answer correct which is your finger and string.
6. Lead students to the conclusion that sound travels better through a solid which is your finger and a string.

The second way to demonstrate this is tying two strings to a metal coat hanger. A plastic coated coated metal hanger will work. This time they will put both index fingers wrapped with a separate string in their ears.

The benefit of the spoon is you can do the next experiment with the spoons.
Have students wrap the string attached to the spoon around their index finger and touch their finger to the interior of their external ear. Listen to the sound.
Try a spoon with a different length of string.
Does it have a higher or lower pitch?
Short string will have a higher pitch than a longer string.
Take time to discuss the difference between Pitch and Loudness.