Put 25 (some coaches say 20, but I say 25, makes the change happen faster) on m2m defense to up their IQ's. When the IQ's get to C/C+ range you can switch over your primary D-Fence to Man to Man.
To note, if you can play the freshman sparingly until then (which by the sounds of it with 5 SR's you could), I would. That way the 5 SR's can carry you to a few victories before the IQ's can carry over and you can switch defences.
But I would recommend switching all of your practice minutes into m2m D and then switching it over as your primary D once the IQ's reach C or C+.