Level 6: A task for blockers and bombers[edit]
Make the first lemming a bomber as he enters the level. He will blow a hole through the floor that the others will fall through. Now set up a blocker next to the thin wall blocking the exit and bomb him, as well. The explosion will free the path to the exit, saving 48/50 (96%).
Level 7: Builders will help you here[edit]
Make the first lemming build a short distance before reaching the short wall blocking the path to the right. One bridge should be enough to get up to the top of this wall. The lemmings will walk up some steps to the right and will eventually reach a pit, which they must build over. Make several lemmings build so that nobody falls in the pit, and you'll have 100%. (If one or more lemmings does fall in, simply build a zigzag set of ramps up the pit, then they will climb out and you will still get 100%.)
Level 8: Not as complicated as it looks[edit]
All you have to do here is let the first lemming walk a few steps and then block. This saves an easy 79/80 (98%), although advanced players will be able to save 100% by freeing the blocker in the end.
Level 9: As long as you try your best[edit]
Have the basher skill ready to use and when the lemmings approach the wall, start clicking on them rapidly to make a bunch of lemmings bash. With luck, nobody will turn around and you'll have 100%. If a few lemmings turn around, place a blocker just to the left of the entrance to keep them from bumbling into the trap.
Level 10: Smile if you love lemmings[edit]
Make the first lemming dig shortly after he hits the ground. One lemming will step out of his hole; make him a floater. When he lands on the ground below, make him block. When the digger is about two thirds of the way through the block, make him mine. The lemmings should drop safely to the ground, bounce off the blocker and head to the exit, saving 19/20 (95%). 100% is possible here for advanced players.
Alternate solution[edit]
Make the first lemming a blocker, then make all the rest floaters. Be quick to swap commands, and you'll need to "catch" one or two in midair before settling down to click the rest as they emerge. Even if you miss a few, you'll be comfortably over the survival percentage.