Answer: It's great to encourage students to design their own experiments and learn to observe!
In their dry state, seeds are in a sort of "suspended animation". Then, once they are exposed to moisture, they begin to swell and the tiny embryo within starts to grow. Seeds do have food storage structures called cotyledons. In fact most of the bean seed is made up of these storage structures. This provides stored food so the plant can sprout and develop its first leaves, when it can then begin manufacturing its own food through photosynthesis.
I honestly don't know if he will find any differences in the liquids. Some liquids may be more readily absorbed by the seeds than others. Some may damage the tiny embryo and emerging roots and shoots.
I suggest you keep the seeds out of sunlight until they germinate, because they don't need light until they are growing, and too much light and heat will quickly dry them out.
I hope this helps!
Q&A Library Searching Tips