Why do we call it "Maundy" Thursday? This is not only the night on which Jesus instituted communion, our sacramental way of experiencing the grace of what crucifixion and resurrection means. It is also the night Jesus gave us a new and very important commandment, that we love one another (that's not so new) as he has loved us (that's the part that's new). According to the fourth gospel, Jesus washed the feet of his disciples, taking on the role of a servant, and instructed them to do the same for others. The word "Maundy" comes from the Latin word mandatum (from which we get our English word "mandate"). It is usually translated "commandment," from John's account of this Thursday night.
Why do we call it "Good" Friday? What is good about the suffering and pain of a cross? Only a poor understanding of the atonement would assume that for a brief moment God lost control and the devil won, as if God was helpless to prevent tragedy but then made a comeback. No, out of the extreme and mysterious goodness of God, self-giving love was ultimately expressed in body broken. Christ willingly went the distance for us to pour out the heart of God, redeeming us by his blood.
Don't skip from Palm Sunday to Easter. Go the whole journey.