Linked lists. Recursion. Calling by reference. Strong typing. Explicit declaration (or at least the need of it). There are some ways around those, but these hacks are even going to warp their minds worse than not learning those things would.
You certainly don't need to learn those things in your first semester of programming.
Now that's impossible.
On my knees under a desk, up under a cabinet, upside down behind a shelf, etc. I used to think its more work moving it from the location its in to a table. Amazing what 5 years teaches you:P