The Sun

Teacher Tips

Hook

• It helps to reveal the answer to the hook (spectroscopy) only after learners have had a chance to discuss, debate and disagree.
• “Send a probe” is a response worth staying with rather than moving past. You might ask “How close could a probe actually get?” Someone may know about the Parker Solar Probe, which flew through the Sun’s outer atmosphere, and they’d be right. It still can’t reach the core, though, and it tells us nothing at all about a star in another galaxy. That is the gap spectroscopy fills.
• If someone says “guess from the colour”, it’s worth saying out loud that they’re the closest. Colour is a crude version of the real method, and a learner who hears their answer was nearly right tends to stay with you for the next twenty minutes.

ITZA Pathways

• It helps to listen for the word “burning”. Learners use it casually about the Sun, and it carries a whole wrong model with it: fire, oxygen, fuel being consumed. You might ask “What does fire need that the Sun hasn’t got?” No oxygen, no burning.
• Pathway 1’s layers hotspot is the card that gets clicked through fastest, and the fusion slider is the one worth stopping at. “What is actually lost when hydrogen becomes helium?” works well here. The answer is a small amount of mass, and it leaves as light.
• Pathway 2 has a true or false on whether heavier elements mean an older star. Nearly everyone answers wrong first time, and it’s the one idea in this session that is exactly backwards rather than merely fuzzy. It’s worth catching it here, because it tends to reappear in every answer during the activity.

Classroom Activity

• It helps to do the practice star with the whole class before letting pairs loose. It looks like a slide you could skip when time is tight, but learners who haven’t watched you match a pattern once tend to declare an element present on a single coincidental line.
• You might find it works to ask for two or more matching lines before anyone claims an element, and to ask “What’s missing as well as what’s there?” Star B is identified by the absence of heavy lines, not the presence of anything, and that’s a harder move than spotting a match.
• The mystery element slide is the best challenge in the session, so it’s worth not rushing to the reveal. You could ask “What should a scientist do when the pattern matches nothing in the library?” The honest answer, that the library is smaller than the universe and you go and find a bigger one, is a better lesson about science than any of the correct identifications.

Plenary

• The lock-in quote is from Carl Sagan, the astronomer and science communicator. It says that the nitrogen, calcium, iron and carbon in our bodies were made inside stars. That’s the “inherited” idea from Pathway 2 in a single line, so if there’s time you could ask two or three learners “Where did the iron in your blood come from?”
• Part 2 will fill with facts unless you say otherwise. It’s worth stating plainly that you’re asking what they think, not what they remember, and that “it doesn’t change anything” is a perfectly acceptable answer if they can say why.