Richardson, a 6-3 senior who has signed with Ball State, poured in 25 points to lead the Chargers to the win in Ligonier.
Cara Hoffman had a big game for the Vikings with 23 points. Valley trailed just 53-49 after three quarters before the hosts outscored them 22-13 in the final period of play.
Kelsey Ball netted 16 points and Caylie Teel added 12 for Valley, which drops to 4-7 on the season.
Kelsie Peterson scored 19 points and Ashley Shepherd hit four treys for 12 points for West Noble, which improved to 9-4 with its fifth straight win.
Valley plays at league foe Northfield Thursday. West Noble hosts Lakeland Friday night.
Whitko went 1-1 in the two-day North Miami tournament that concluded on Saturday. The Wildcats beat the hosts 51-40 on Friday and then lost 60-59 to Peru Saturday.
Whitko, now 5-8, plays at Rochester Saturday.