Each student was given Wikki Stix (pieces of string covered in wax) and a dry erase marker. Teachers drew several different triangles on the board. Students formed the same triangles on their desk tops with Wikki Stix. Using the dry erase markers, students wrote directly on the desk tops to label sides, angles and use formulas to determine sine, cosine and tangent.
We saw 100% participation! Students were jazzed about having permission to write on their desks - it hooked them by having a slight "rule-breaking feel" to it. Forming the shapes with the Wikki Stix kept the students thinking in a hands-on way. And the very visible nature of the work made it easy for teachers to quickly see which students understood the concepts.