The other tool for solving problems in this minimalist spreadsheet environment is the ability to create multilevel functions. Depending on the age group to which Sprego programming is introduced,

• the phenomenon of function and multilevel function would be familiar, and with Sprego word problem solving based on authentic data would be learnt,
• Sprego programming can be used to introduce the phenomenon,
• it is an environment enabling us to practice how values would be transferred from the internal function to the external function, and to understand the relation between the domain and range of the functions in this hyponym and hypernym relationship.

In this approach to spreadsheet management students understand that functions in a formula can be embedded into each other. The output of the innermost function is the argument of the function around it; its output value is the argument of the next function around it, and so on, until we reach the outermost function, whose output is the output of the whole multilevel formula. The functions hold each other just like the popular matryoshka dolls do.

The realization of the multilevel functions should follow the evaluation order. This means that first the innermost functions should be constructed and evaluated. If this is done correctly, we can expand the formula and the results appear in the same array. Here we create the function outside to the first one, using its output value as an argument of the outside function.