Although this reaction looks like this is a case of a neutralization reaction, which are usually exothermic, this case is a bit more complicated than that. The reaction is indeed endothermic (you, probably, observed that the temperature in your beaker dropped down significantly when you did the experiment ;)
The calculations for the exact amount of heat absorbed are rather straightforward if you use the standard calorimetry calculations (remember equation for specific heat?). You can double-check your calculations or see how accurate those are by calculating the ΔH° of this reaction via the Hess law.
If you feel like you need more help working on this problem, feel free to contact me directly!