Mike Reeves has had a big impact on us in UCCF over the last couple of years in his role as our Theology Advisor. I think he's helped us particularly in four things.
1. Helped us see theology is exciting.And the Trinity stuff is essentially available here -
2. Church history. Particularly his love of Luther.
3. Doctrine of creation - which gets Jesus' rule over all of life not just some narrow piety. It recovers art and study, humanity and enjoyment as part of Christian life. Sanctify the ordinary!
4. Trinity. Easily enough for a six year old. Do away with the absurd illustrations about impersonal objects like clover leafs and water and eggs. If you want to know what God is like read the Bible - and if something in creation must illustrate God then it'll be the climax of creation (humanity in relationship).
Depending on the living God (includes outline of talks)
MP3s: Session 1, Session 2, Session 3.