Subtract the ones:

Next, we do the tens stripe...  Remember that the 3 is crossed out, so ignore it!  We can't do 2-5, so we'll need to borrow from the hundreds stripe!

Now, we can subtract the tens stripe... and the hundreds stripe:

Don't worry if your head is swimming on these problems...  That's normal!  Hey, there's a LOT going on here to get used to.  But, you WILL be able to get it.  The more you do, the easier they'll get!  I've got some good practice problems for you on the next page!