insert values into sqlplus database using shell script

hello all,
I am new to shell scripting and to unix... so the following is my assignment..

here i am trying to insert a values into sqlplus database using shell script.

the following is my shell script
InsertDelete.sh

#! /bin/sh

echo "*The MENU
1.Insert The Values Into DataBase
2.Delete The Values From DataBase
Enter Your Option:"

read choice

case "$choice" in
1)echo "The Insert Operation"
echo "Enter the Name"
read name
echo "Enter the age"
read age
sqlplus scott/tiger @secondScript.sql;;
2)echo "The Delete Operation";;
*)echo "Invalid Operation";;
esac

and this is my secondScript.sql

DEFINE name=$name
DEFINE age=$age
SPOOL secondScript.lst
SET LINESIZE 100
SET PAGESIZE 50
INSERT INTO PRADEEP_DATA (name,age) VALUES ('&name','&age');
commit
SPOOL OFF

The Problem is the values of name and age, is not passing to the .sql file ?
and when i check the database,
instead of values for name and age
$name and $age is inserting into the database!!

can anyone help me in this regard... ?
thanks in advance !!!

Posting homework questions are against the rules...

Closing this thread. Violation of "No Homework" rule.