I dont know who you're teacher is, but i think he did a mistake..
The Format for a bank reconciliation statement show up like this:
$ $
Balance as per Bank statement xxxx
Add Amounts not yet credited
xxxx xxxx
Less Cheaques not yet presented
xxxxBalance as per cashbook
xxxxThats all.
About the errors:
I dont understand what do you mean about "the errors we find in updating the cashbook" can you explain more and Ill try to help you.
you look like a hard worker, we still have about 12 days for accounting and your working

Note: xxxx means a random number k?
hope I helped,
AL*Eagle