Bb Clarinet. Two (D) and three ledger lines above the staff (E). More clarification. I'm trying to play eight staccato 8th notes (D) in succession and eight staccato notes in succession (E). I also need to be able to play three adjacent staccato notes: D (two ledger lines above the staff) to G (4 lines above the staff) back down to to D (two ledger lines above the staff).
That sounds a bit challenging. My best advice would be to start very slowly on just D doing the tut tut tut thing. Then slowly doing the same thing on E. After that perhaps alternating notes. The G is a tough one, but once you have the D and E under control it may be a bit easier.
Another exercise might be to play long short long short (tah tut tah tut) over and over to get a feel for the difference in tonguing.
Disclaimer: I used to be a pretty good clarinet player 20 some years ago, but I have let my skills slip due to a major focus on sax.
Your post made me pull out my Kell Staccato Studies book and have-at-it!
High D/E (on your Bb clarinet) shouldn't be much different from staccato tonguing
if you are raising the back of your tongue to bring the pitch up (from your clar high C on up) and in doing so that would change the orientation (position) of the tip of your tongue
raising your tongue too much will impede your air-flow somewhat.
When staccato-ing I concentrate on the rebound of the tongue, not so much the attack.
The less-tongue you use the better.
Tip of the tongue to tip of the reed!
As an aside, I had to pull out the clarinet a couple of weeks ago to play Hava Nagila for a wedding. It's a good thing I started working on it two weeks before, because my clarinet chops had deserted me after a long layoff. I managed to get through it after some practice. Now I'm afraid to pull out the bass clarinet because I haven't played it in over a year.