Set-up prior to experiment: one hour before students come into class, set up a habitat for each table group. Each habitat is a clear container with a layer of damp sand on the bottom, a chunk of rotten wood, a rock and five wood bugs.
Students are shown a habitat, and told that we will count how many wood bugs are in each place:, under the wood, under the rock, and out in the open sand. This will show us what kind of hiding places, if any, to put in our wood bug habitats.
Optional prediction: Students are asked to predict whether wood bugs might prefer to hide under the wood or the rock, or stay out in the open sand. For younger age groups it is best if predictions are done anonymously: ask students to close their eyes, and vote by raising their hand. Class predictions are recorded on the board. (Note: I would recommend skipping this prediction step if the students have not already done a lot of hands-on science with careful observation and recording already. Accurately seeing and recording scientific phenomena is the first step to be mastered, before adding the complexity of thinking ahead and predicting).
At their desks, each group counts how many of their five wood bugs are under the wood, how many are under the rock and how many are out on the open sand.
They record their results by using one stickie per wood bug, and writing where they are on it (sand/wood/rock). They can also record on a worksheet for a science notebook. Each group adds their data to a class bar chart. The bar chart has number of wood bugs on the upright axis, and three categories along the base of the chart: under the wood, under the rock, on the open sand. The stickies can be added directly to the chart to build the columns. (For the classes I worked with 90% of the wood bugs were under the rotting wood. The remainder were out in the open sand).
Students adapt their habitat in response to the results. (The rock was removed from our habitats).
Discussion on why the wood bugs prefer the rotting wood and sand (this is the result we got every time so far). The sand is damp and they can bury into it. The wood is a shelter, it is damp so keeps them moist, it is dark under the wood, they might also eat the wood.
Conclude that we have given the wood bugs a shelter that they like in their habitat.