YA fiction

There are two books of young adult fiction I read in gradeschool in the early 90s. These books could be from before then. I remember I really liked them, but I can' bring up anything except sketchy details.

The first involved one or two young boys who had a cloak of invisibiliy and were hiding from someone in a building and there was snow outside. I told you the details were sketchy. Any ideas what I'm talking about?

The second book involved a male protagonist and his party and their adventures in some other world.  The only thing I remember about this was that there was a lake he became trapped under and couldn't resurface and all the while his party were blissfully unaware.  Also the book was a blue color.

Help, /Books, plzzzzzzzzzz!

err the first one sounds like harry potter, although I'm sure you wouldn't forget the name of that.

I think the first one was called "The Cloak of Invisibility" and the second one, if I recall correctly, is called "The Boy Trapped Under the Lake"