Science in term two was based on the chemistry of heating things up and how objects and material changed with heat.
We had some starter discussions on how livings things might keep warm.
This got us thinking of how we could keep warm, if we were very cold.
After a short discussion on heat sources, areas that produce warmth or heat, we began looking for these sources of heat in our classroom. I added some extra ones for comparisons.
In our search we needed to decide on a heat rating was the object warm, hot or very hot. We shared our investigations and recordings to see if our team mates agreed or disagreed.
We learned that heat (thermal energy) can be classified according to its form and there are three to know and understand.
Our next challenge was to put some understandings into action. We really enjoyed our investigation using metal spoons. In teams we used a metal spoon to heat up at our choice of six different heat sources. Areas to be accessed included – urn/kettle, cups of hot water, hair dryer, candle, white board/other electrical objects, carpet, body heat, hot water bottle. We shared roles for heating and timing and to make our investigations fair, we used a stop watch to time the duration at exactly two minutes. That way we could compare the different types of heat. Warnings were given as science investigations can be somewhat dangerous, particularly given we were using a flame, metal can get very hot!
This investigation gave us lots to think about how heat might travel or transfer into or up objects. When could that be a good thing? Who would need this to happen? Why? When do we not want heat to transfer quickly or at all? Do we know of any situation where they have seen this?
We also challenged ourselves to decide what type of heat source it was chemical, kinetic or electrical.
Recording our observations gave us a chance to sharpen our science line drawing skills.
During this activity a few of our classmates did get too excited and forgot the warnings, burning themselves on very hot metal spoons. It seemed appropriate that we look at warning signs and posters checking to see what essential information we may need to include if we were to warn people of, very hot sand, hot cup of tea or a hot frying pan. Working with a partner we used our negotiating skills to plan and display our thinking.
We got a chance to explain the message behind our posters before we placed them on display.
Our final investigation made us think carefully about variables. We wanted to know what would affect the heat of a spoon in a cup of hot water.
I thought we showed critical scientific thinking as we suggested that these things would affect the temperature :-
- type of material spoon was made out of
- the time the spoon was left in the water
- the temperature of the water
- the temperature of the spoon
- the size of the spoon
Teams worked together to plan our investigation.
Essentially we needed this information. We were able to use a wooden, plastic and metal spoon to compare results.
Unfortunately Ellen was so busy making sure we didn’t have any injuries this time, so she wasn’t able to visually record our work.
However it was interesting when we completed our work to find that most of our predictions were accurate. One team took a very long time to complete their plan and by that time the hot water had cooled down quite a bit. Time did play an important role in the hotness of the spoons, however so did the material that the spoon was made of.
This gave us lots to think about when using objects near heat. Many students could see connections to tools used in their families kitchens. Wooden spoons are very useful when stirring hot food. Perhaps plastic tools could be used too. Some discussed how they have metal tools but handles are wooden, that made sense given our new understandings.
Our last opportunity to put our new learning into action was to identify heat sources in a picture. It was amazing how many were in one little scene from a family’s kitchen and outdoor area.
What did you enjoy most about the Heating up unit?
What questions do you still have about heat?
How have you used your new knowledge on heat lately?
How did you go locating all the heat sources?