We started a multi-day project. We’re going to try to relate rocks and weathering to the streams and simple filters that I’ve been talking about in the past few weeks.
I asked the kids how many knew where Muncie Creek was? Nobody. I asked them a different question, “how many of you have been to the creek behind the school? The one that runs behind the football field and down through the little park there?” A few. “Who knows what the name of that creek is?” “Muncie?” AH HA!!
I went down to the creek. I noticed that there are lots of different rocks of different sizes, and I said to myself, “I wonder how much of the rocks are at each size?” I asked the kids how I might answer that question. Some said count them. Some said measure them. Then I showed them my bucket and spoon and some of what I had collected in a clear jar. I asked them how should I measure the really small stuff like sand and silt? Should I try to count each piece or measure it with a ruler? And how should I separate the sand from the silt and those from the gravel?
Over the next several weeks we’re going to try to answer my question. For the introductory lesson, I scooped up some sediment, made some mud pies, and dried them overnight. There is a standard scientific method for this that I will stress later, but for now dried mud pies is close enough for my purposes. We’re going to sort the sediment using standard sieves (ooh simple filters!), and use percent weight to quantify how much of the sediment is in each size category.
My two other goals are (1) to get the students to start thinking about this stream, because we’re going to go out there later in the semester, and (2) to keep building a context of information for the students to ask their own questions later. For example, Mrs. Loeffler’s kids have already asked me, “What does sediment look like?” “What color is sediment?” “Where does sediment come from?” I’m hoping that the students will be able to focus in on something in this stream system that might interest them enough to develop and test their own questions later in the year.