I never got on with "Wrinkle." But YA - what about Harry Harrison's Stainless Steel Rat series? I got a whole lot of enjoyment from those in early high school. Originally written more than ten years before I got to 'em. '61, I think. "Slippery Jim" diGriz. Fond memories. Haven't reread them since. Next zoom to the local library, I'll check to see if they have 'em - though I'll want to scan them first. Some things should be left in childhood, so as not to ruin the memories.