Telling the difference between toad and frog spawn is very simple, you just need to look at its shape.
Frogspawn is laid in big clumps of jelly, whilst toads lay long strings of eggs - a bit like a pearl necklace. You can easily distinguish between toad and frog tadpoles a few weeks after they hatch. Toad tadpoles remain jet black, whereas frog tadpoles are mottled greenish grey with gold speckles.