There are several types of visa which may be relevant to Russian families who are considering educating their child in the UK.
Child Student: up to the age of 18, the visa is known as a “Tier 4 (child)” which must be sponsored by a licensed education provider (the school) which has issued a “Confirmation of Acceptance of Studies” – a firm offer of a place at the school. Many independent schools hold the required licence. If the child needs to attend the school for an interview before a place is offered, a “prospective student” visa may be issued for the visit.
Parental visits: if the child is under 12, there is a special class of visa which can be applied for as the “Parent of a Child at School”, which lasts for 12 months and which can be extended.
For older children, a parent must apply under the “Family Visitor”category, which can be granted for multiple entries for a period of years (with visits limited to 6 months).
Camelot Studies can recommend both Russian and English legal specialists to help you.