Complete Asami Blossom Lessons.
During day go to the map and click the watch in lower right corner to start the
quest.
You will have a chat with Opal. Go to Pema's room and start the quest. Next evening, go talk to Sandy in Blue Movers. Next day, talk to Raiko at City Hall. You may choose to warn Tenzin or not. ( To open Pema's cheating route, you must warn him)
Tried these?