We investigate the problem of exactly identifying a real-valued function of {0, 1} n represented by a weighted sum of a number of monotone terms by querying for the values of the target function at assignments of the learner's choice. When all coefficients are nonnegative, we exhibit an efficient learning algorithm requiring at most ( n − ⌊ log s⌋ + 1) s queries, where n is the number of variables and s is the number of terms in the target formula. We prove a lower bound of Ω( ns log s ) on the number of queries necessary for learning this class, so no algorithm can reduce the number of queries dramatically. The algorithm runs in time O( ns 2) in the worst case. The same algorithm can be used to learn the ‘inductive-read- k’ subclass, a proper super class of the ‘read- k’ subclass, with a number of queries not exceeding 1 2 ((n − ⌊log k⌋)(n − ⌊log k⌋ + 1) + 2)k , which improves upon the bound achievable by a naive learning algorithm by a factor of two. In addition, the above method can be extended to handle the nonmonotone case in some restricted sense: A similar algorithm can learn the unate linear combinations of terms with a comparable number of queries. In the general case, namely, when the coefficients vary over the reals (or any arbitrary field), we show that the number of queries required for exact learning of the k-term subclass is upper bounded by q( n,⌊ log k⌋ + 1) and is lower bounded by q( n,⌊ log k⌋), where q(n, l) = ∑ l i = 0 ( n i) . These bounds are shown by generalizing Roth and Benedek's technique for analyzing the learning problem for k-sparse multivariate polynomials over GF(2) (Roth and Benedek, 1991) to those over an arbitrary field.