Building an Earth Oven

Yesterday we "baked" in our Tiny Cookie Oven!

I chose an eggless recipe (Eggless Chocolate Cookies) in case the cookies did not bake thoroughly -- which they didn't -- but the children still wished to try them. They described them as tasting of "fudge with ashes." This did not dissuade them from wanting to build an even bigger one and try again!

Kiko Denzer advises folks to not spend forever in background reading but to just put your hands in earth and get started with a tiny oven, one just big enough for a muffin. After building the first attempt, you'll have a lot more know-how and you'll be in a good position to make a more advanced design. The hardest thing is to just get started!

Notes from this project:

week 1 - read sections from The Hand-Sculpted House: A Practical and Philosophical Guide to Building a Cob Cottage by Ianto Evans, et al. and make several shake jars to test our soil

week 2 - read sections from Build Your Own Earth Oven: A Low-Cost Wood-Fired Mud Oven by Kiko Denzer, et al., dig our clay, and wait for the rain to stop so that we can begin building

week 3 - give it a whirl!

Monday - try #1
turns out that the mud layer is 3 parts sand to one part clay and I had read it as the other way around! I did not purchase enough sand so we had to pause until I got more

(we got our sand for a dollar a bucket from Ready Mix... head up Oakland until you see it on the right)


Tuesday - try #2
we built the form, did the wet newspaper step, built the mud layer, and cut the door

then I misunderstood the directions and we tried to immediately remove the sand form

the roof fell in (of course) so we had to rebuild it

now I know that the mud has to make a crust first (wet newspaper is not strong enough to hold up the arch on its own) and next time I will have us make Homemade Magic Shell to better explain it


Wednesday - try #3
the mud oven was damaged in the rain so we had to rebuild it


Thursday
the oven was not yet dry

week 4 - complete the oven and try baking!

Monday - try #4
the mud oven was damaged in the rain again (the cover we put on blew off during the big thunderstorms) so we had to rebuild it


Tuesday
dry! we scooped out much of the sand



Wednesday
still dry! we are finally catching a break in the weather

we removed the rest of the sand, tickling the inside of the oven with our fingers to loosen it and stopping when we hit the newspaper

I built a small fire inside the oven to dry it the rest of the way



Thursday
still dry! we tested the oven today for the first time

One of my students carefully described all the steps to me for his MLB and you can see how clearly the process stuck with him:

We also spent our time this month practicing units of metric measurement for volume and mass, enjoying some vintage flashcards. We looked at the connections between the metric system and our Montessori math manipulatives for place value (stamp game & decimal stamp game).

We also found some connections between the metric system and our box of Cut-Out Labeled Fraction Circles.

AND we played the always popular Estimation Game! Each morning for two weeks I set out an item and the children had to estimate its mass in grams. Each day's item was then written down and they could compare new items to information they already knew... carefully holding them in their hands... to help them fine tune their estimates more and more as the days went on.

Our list of items was

paperclip 1 g

nickel 5 g

cotton boll 6 g

Chill Pill essential oil roll-on 35 g

chalkboard eraser 43 g

wooden fox 48 g

wooden pig 111 g

red duct tape 124 g

clay pot 192 g

Play with Plants by Millicent Selsam 248 g

clay pot with green colored pencils 375 g

Colored Globe of the Continents 521 g

The earth oven was definintely a challenge to build but so totally worth it. Just look at how happy they were!

If you visit Fort Massac, by the way, their oven works the same way. You build the fire, heat the masonry thoroughly, blow out the fire, swiftly remove all the ashes, and put in your baked goods. Then pop on the door and let the oven cook via residual heat.

This kind of oven was essential in colonial times in the U.S. It is also why you hear of the big community ovens not being used in the wintertime. It was just too cold outside for the oven to get as hot as was needed. Thus the importance of boiled bread, ash cakes, hoecakes, etc.

Both of our historical fiction books that take place at Plimoth show this kind of oven in use: Stranded at Plimoth Plantation 1626 by Gary Bowen and Goody O'Grumpity by Carol Ryrie Brink.

So even if my students never build an earth oven again, they deeply understand what it takes to do so, how it works and why... and beyond the practice with measurement, they had a little taste of history as well.

This post contains affiliate links to materials I truly use for homeschooling. Qualifying purchases provide me with revenue. Thank you for your support!