Dr. Alexey Root showed a position where a queen and rook checkmated a lone king (just the final checkmate position). Then she asked pairs of students to try to set up a checkmate position using the White (Q, R, and K) against a lone black king. Some beginner misconceptions were revealed, such as putting a king next to a king or thinking that if you put an undefended queen next to a king that would be checkmate.
Intermediate students were shown how to checkmate with a king and queen against king which pairs then practiced. Dr. Root continued testing individual students (on King and two rooks vs. King checkmate from last week).
Advanced students were shown how to checkmate with a king and rook against king which pairs then practiced. Dr. Root tested individual students on the king and rook vs. king checkmate.