As part of their themed topic 'Go with the Flow' (Rivers from Source to Sea) they visited a stream high up in the Dubravka forest to test their model boats for speed and buoyancy. The children built dams in the stream so that they could float their models and time how fast they could travel down a measured distance. The tests were followed by a hike to the 'Indian Camp' - an ancient rock formation on the top of the mountain, where the children studied closely the fauna and flora found at high alpine locations where rivers commonly begin as springs and small streams.