If you would like to manually manage when your kids receive their allowance, you have the ability to switch off allowance being delivered automatically.
To do this:
Tap Menu in the top right corner of the family dashboard
Tap Manage Account
Tap on the name of the child who's allowance you wish to switch off
Tap Allowance settings
In the field with the allowance frequency, click the drop down and select Allowance not set
Alternatively, you can also do this by following the steps below:
Go to your child's dashboard
Click on the 'settings' cog in the top right
Tap on your '[Child's name] Settings'
Click on 'Allowance settings'
In the field with the allowance frequency, click the drop down and select 'Allowance not set'
This will remove your child's allowance, allowing you to manage this manually through 'Boosts'.