In most British schools in the 1980's and 1990's BBC B and BBC Master microcomputers (made by Acorn) were king, their dialect of BASIC is second to none and with disk drives loading times were significantly faster than other 8 bit machines such as the humble Speccy and the Commodore 64.
I'm not sure if a hand held would be possible, as these featured more components than a Speccy, (including plug in eeprom sockets for built in software), but I'm sure there's room to reduce the size of the system and it should prove quite a technological challenge.