How much heat is needed to melt chocolate?

Last week Matai tamariki investigated heat energy.  They created their own solar pizza ovens and explored how long it would take to melt chocolate buttons on a biscuit.  Luckily the spring weather gods were on our side and we had a lovely sunny day to test our prediction that the chocolate would melt.  

Like with all science experiments we had lots of "wonderings"; 

* How much heat is needed from the sun to melt something?

* How long would it take to melt?

* Where would be the best place to put our pizza ovens?

* Will it even work?

Everyone placed their own biscuit and chocolate in their "ovens" and started recording their observations at 2 minute intervals - what can we see happening, are there any changes?  The outside temperature was 20 degrees and it only too 21 minutes to melt the chocolate!

We discovered the chocolate was really hot to touch and delicious - we can't wait to try this again!