How do I do a bookkeeping only transaction -- No cash changes hands. ?

unknown

Quicken Windows 2017 R16.2

I have given my teenage son an advance on his allowance.  Let us say the advance is for $300.00. He is to "repay" the advance by me simply deducting $10.00 each week from his allowance. 

For example each week his CASH allowance would be $50.00 less $10.00 for a total of $40.00

What is the  best way to record the weekly transactions since the only cash withdrawal from my bank account is for $40.00?  The $10.00 is only a bookkeeping transaction. I do want to be able to track the repayment of the advance so I can show him (as part of his money management education) a copy of the transactions.

NotACPA

How do you normally record his allowance?
Because, the original $300 would be a transfer from one account (checking?) to another asset account, that you create.
Then, when you record the weekly allowance, do a split transaction:
$40 Transaction amount
Split 1: $50 to whatever category you use for his allowance
Split 2: -$10 to that 2nd asset account ... reducing it's balance.