An useful application of computer algebra systems is the generation of algorithms for numerical computations. We have shown in SIAM Review Vol 41, Number 3, Sept. 1999 how computer algebra can be used in teaching to derive numerical methods. In this paper we extend this work, using essentially the capability of computer algebra system to construct and manipulate the interpolating polynomial and to compute a series expansion of a function. We will automatically generate formulas for integration and differentiation with error terms and also generate multi-step methods for integrating differential equations.