INCOME TAXES (Details) - USD ($)	12 Months Ended
	May 31, 2020	May 31, 2019
INCOME TAXES (Details) [Line Items]
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	21.00%	21.00%
Deferred Tax Assets, Valuation Allowance	$ 3,175,000	$ 2,459,000
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount	716,000	$ 900,000
Domestic Tax Authority [Member]
INCOME TAXES (Details) [Line Items]
Operating Loss Carryforwards	9,213,000
California State Income Tax [Member]
INCOME TAXES (Details) [Line Items]
Operating Loss Carryforwards	5,025,000
Research Tax Credit Carryforward [Member] | Domestic Tax Authority [Member]
INCOME TAXES (Details) [Line Items]
Tax Credit Carryforward, Amount	438,000
Research Tax Credit Carryforward [Member] | State and Local Jurisdiction [Member]
INCOME TAXES (Details) [Line Items]
Tax Credit Carryforward, Amount	$ 160,000