I teach 6th grade Confirmaiton. For my kids I would put it this way:
Grace is a gift from God that gives us the ability to follow His ways.
Sanctifying Grace is the grace which God gives us which allows us mere mortals to partake in His Divine life. We get this grace at baptism and but we lose it when we willfully reject God via mortal sin. We regain it at reconcillation.
Actual Grace is the strength to follow God.
For example: I have lost sacntifying grace by my own fault because I am in mortal sin and cut off from God. Knowing this, I go to confession. At absolution God’s sanctifying grace again flows into me and I have the strength to again take up my cross and follow him. Leaving Church refreshed, I decide to head out for lunch as I am starving. I see a homeless man. I know that Jesus wants me to take care of my homeless brother and not pass him by, but man I am REALLY hungry. Actual Grace is the stength God sends me to do what Jesus would want and take my meal money and give it to my homeless brother.
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