\environment math-fonts-helpers

\startbuffer[scripts]
    \ruledhbox{$\textstyle         x\char"207A x\char"207B x\char"208A x\char"208B$}
    \blank
    \ruledhbox{$\scriptstyle       x\char"207A x\char"207B x\char"208A x\char"208B$}
    \blank
    \ruledhbox{$\scriptscriptstyle x\char"207A x\char"207B x\char"208A x\char"208B$}
\stopbuffer

\starttext

    \MathSamples [
    ] [
        scripts
    ]

\stoptext