variable in from clause

Evlich is correct.

If it helps in the future, you may want to break things down into smaller pieces:

' First define constants which can be carried from code to code or defined globally
Const cSelectVerb as string = "SELECT "
const cFromVerb as string = " FROM "
const cWhereVerb as string = " WHERE "

' Now define variable pieces:
Dim strSelectFieldList as string
dim strWhereClause as string

strSelectFieldList = "Password,Number, First, Last  "
strWhereClause = cWhereVerb & "First = '" & TeacherFirst.Text & "' and Last = '" & TeacherLast.Text & "'"

' Now assemble all the pieces:

Set rs = dbmath.OpenRecordset(cSelectVerb & strSelectFieldList & cFromVerb & TableName$ & strWhereClause)

--
And if the where clause gets too complex, you could break that down in the same way as the select:

const cFieldName1 as string = " First "
const cFieldName2 as string = " Last "
const cAndVerb as string = " AND "
const cEquateVerb as string = "="

dim strFieldValue1 as string
dim strFieldValue2 as string

strFieldValue1 = "'" & TeacherFirst.Text & "'"
strFieldValue2 = "'" & TeacherLast.Text & "'"

strWhereClause = cWhereVerb & cFieldName1 & cEquateVerb & strFieldValue1 & cAndVerb & cFieldName2 & cEquateVerb & strFieldValue2

--
This may look confusing at first, but it's general-purpose enough that you could turn it into a function which assembled all the pieces for you and returns the correct SQL string.  That's a bit overkill for simply queries, but if you do a lot, it may be worthwhile.

Thanks you !. It worked.
And thank you too, RSPAHITZ, for helping out someone very new to SQL.
Mathprof