CONSOLIDATED BALANCE SHEETS (Parentheticals) - USD ($)	May 31, 2017	May 31, 2016
Allowance for doubtful accounts (in Dollars)	$ 50,129	$ 8,405
Preferred Stock, No Par Value (in Dollars per share)	$ 0	$ 0
Preferred Stock, Shares Authorized	5,000,000	5,000,000
Preferred Stock, Shares Issued	0	0
Preferred Stock, Shares Outstanding	0	0
Common stock par value (in Dollars per share)	$ 0.08	$ 0.08
Common stock, shares authorized	25,000,000	25,000,000
Common stock, shares issued	8,511,173	8,169,673
Common stock, shares outstanding	8,511,173	8,169,673