All of the above methods require low-firing clay (school pottery clay is fine).
When you first make a model, it is called 'greenware'. A first firing of this creates 'bisque' or 'biscuit-ware'. At this point the model is hard, but still porous so cannot be used with liquids. After glazing, a second firing will create a non-porous pot.
Only the first method of making a kiln will allow you to create glazed items.
Raku is a different method where you remove the pot from the kiln while it is red hot, then plunge into cold water or sawdust. This creates a lovely crackle effect on the glaze. This is really a step too far for a homeschooling project! I have had a Raku expert assure me that this is a very toxic and dangerous technique so you should not try it yourself at home.
Your greenware must be totally dry before you put it in a kiln. This can take up to a week depending on the size of the piece, and the humidity. It is a good idea to pop the pot into an oven for a while to heat it up and make sure there is no more water left inside it, before firing. This should reduce the risk that the piece will crack.
Firing clay at home is very much trial and error. Be prepared for some disasters at first!
Smoke and Pit fired models benefit from being burnished first. Use the back of a spoon to rub the clay and make it smooth and shiny.
Normally a kiln is both heated up and allowed to cool slowly. Try not to allow sudden changes in temperature.
To really add to your homeschooling experience - there is a great chapter about making pots in Robinson Crusoe. There is a children's version of the chapter here.
These methods of firing would make a wonderful project for your homeschool high schoolers. As well as figuring out how to fire the pottery for themselves, there are some great projects you could do with clay.
There are some excellent ideas for high school projects on this blog. Well worth taking a look.
Oh my goodness! I am a home schooling mum of 4 and I have NEVER found a better site! Thank you so much.
Blessings, Jenny (New Zealand)
I wanted to say THANK YOU for your fabulous website. I found your website, and finally I have the confidence to take the plunge and take my daughter out of school and educate her at home, thank you, thank you. Marina (UK)
I cannot get over how much great information and super ideas you have here. Fantastic! Ruralmama (USA)
This is simply fabulous!! I just now found this site and I'm so excited!! The opportunities and suggestions as well as the need to inspire are exactly what I have been searching to fulfill!! I'm so thrilled to get started and even more excited to continue to explore all of the fabulous suggestions and creative ideas you have offered here!!! Thank you, thank you, thank you! Jennifer (USA)