It's wrong to demean a gender.
Wally is the debate team manager and is in charge of picking the team lineup.
Wally wants to choose students for the debate team.
Wally chooses the debate team lineup based on performance regardless of gender.
Wally only chooses boys for the debate team lineup because he thinks boys are smarter.
The debate team will have a higher chance of winning.
The debate team will miss out on potentially intelligent members by only choosing boys.