Model rocketry when done safely and correctly is great at all ages. Of course you will want to apply some adult supervision for very young children.
Most rocket manufacturers suggest adult supervision under 10 or 12 years old.
Of course not all rockets and motors are the same and higher power motors may warrant waiting to be even older to fly without supervision.
A and B motors are great starter motors so it may be worth picking starter sets or rockets and motors in this category for younger children.
Regardless of the age using of rocket motors you need to be at least 18 years old to purchase and store any rocket motors in the UK.
We suggest parental guidance is the key when deciding what age and what level of supervision is required for your children. Ensure your children read and know all the safety information included with the rockets and motors before flying.