IF thisform.Optiongroup1.value = 1
> USE winnings
> INSERT INTO 'winnings' (amount) ;
> VALUES (thisform.text1.value)
>ENDIF

You can try to use this also, or put variables on your textbox valid event..

IF thisform.Optiongroup1.value = 1
        yAmount = thisform.text1.value
	USE winnings
	INSERT INTO 'winnings' (amount) ;
  	 VALUES  (yAmount)	
ENDIF