Cole R. Southall, "Continuing RESPs Beyond the Death of the Subscriber", Canadian Tax Focus (Canadian Tax Foundation), Vol. 8, No. 1, February 2018, p.13

an immediate liquidation of an RESP on death is unnecessary

A registered education savings plan will form part of the estate of a deceased sole or last subscriber to the RESP. Accordingly, the will can allow the executors to continue the plan beyond the death of the testator for the benefit of the beneficiary (and contribute to the plan on the beneficiary’s behalf). This would permit future distributions to qualify as educational assistance payments and be taxed at the RESP beneficiary's low marginal tax rate.

RESP part of subscriber’s estate (p. 13)

Funds invested in an RESP remain the property of the subscriber (the person who established the RESP) until payments are made to or for the benefit of a beneficiary. Thus, on the death of the sole or last subscriber, the RESP will form part of his or her estate….

Estate can defer the arising of income from educational assistance payments (EAPs) (p. 14)

The definition of "subscriber" in section 146.1 includes any other person who acquires the individual's rights as a subscriber under the plan or who makes contributions into the plan in respect of a beneficiary, including the estate of the subscriber. Accordingly, a will can allow the executor or a trustee or other person to acquire the rights of the subscriber under an RESP, or to contribute to the plan on behalf of a beneficiary, in order to continue the plan beyond the death of the testator for the benefit of the beneficiaries of the plan. There is no need to immediately liquidate the RESP and create the associated tax consequences; its continuation, for example, could allow taxation to be deferred and future distributions to qualify as EAPs and be taxed at the RESP beneficiary's low marginal tax rate….